WEBVTT Kind: captions Language: en 00:00:00.000 --> 00:00:19.510 align:start position:0% I 00:00:19.510 --> 00:00:19.520 align:start position:0% 00:00:19.520 --> 00:00:22.790 align:start position:0% yeah<00:00:20.520> and<00:00:20.760> the<00:00:20.820> slides<00:00:21.029> are<00:00:21.150> they're<00:00:21.300> great<00:00:21.800> so 00:00:22.790 --> 00:00:22.800 align:start position:0% yeah and the slides are they're great so 00:00:22.800 --> 00:00:27.290 align:start position:0% yeah and the slides are they're great so yeah<00:00:23.550> this<00:00:23.759> talk<00:00:24.450> will<00:00:24.750> basically<00:00:25.970> yeah<00:00:26.970> I 00:00:27.290 --> 00:00:27.300 align:start position:0% yeah this talk will basically yeah I 00:00:27.300 --> 00:00:29.330 align:start position:0% yeah this talk will basically yeah I just<00:00:27.450> want<00:00:27.720> to<00:00:27.810> tell<00:00:27.930> what<00:00:28.140> we<00:00:28.230> did<00:00:28.410> during<00:00:29.130> the 00:00:29.330 --> 00:00:29.340 align:start position:0% just want to tell what we did during the 00:00:29.340 --> 00:00:31.580 align:start position:0% just want to tell what we did during the last<00:00:29.520> year<00:00:29.939> and<00:00:29.970> what<00:00:30.779> the<00:00:30.930> plans<00:00:31.169> for<00:00:31.380> the 00:00:31.580 --> 00:00:31.590 align:start position:0% last year and what the plans for the 00:00:31.590 --> 00:00:39.280 align:start position:0% last year and what the plans for the future<00:00:31.680> are<00:00:31.950> with<00:00:32.550> regard<00:00:32.730> to<00:00:32.910> solidity<00:00:33.270> I 00:00:39.280 --> 00:00:39.290 align:start position:0% 00:00:39.290 --> 00:00:42.830 align:start position:0% want<00:00:40.290> to<00:00:40.500> start<00:00:41.040> with<00:00:41.130> explaining<00:00:41.880> what<00:00:42.210> what 00:00:42.830 --> 00:00:42.840 align:start position:0% want to start with explaining what what 00:00:42.840 --> 00:00:46.360 align:start position:0% want to start with explaining what what the<00:00:43.050> the<00:00:43.710> initial<00:00:44.070> goals<00:00:44.309> were<00:00:44.760> for<00:00:45.030> solidity 00:00:46.360 --> 00:00:46.370 align:start position:0% the the initial goals were for solidity 00:00:46.370 --> 00:00:50.180 align:start position:0% the the initial goals were for solidity so<00:00:47.370> the<00:00:47.630> the<00:00:48.630> idea<00:00:48.870> was<00:00:49.020> to<00:00:49.050> have<00:00:49.560> a<00:00:49.710> statically 00:00:50.180 --> 00:00:50.190 align:start position:0% so the the idea was to have a statically 00:00:50.190 --> 00:00:53.630 align:start position:0% so the the idea was to have a statically typed<00:00:50.310> language<00:00:51.090> that<00:00:51.510> is<00:00:52.040> easily<00:00:53.040> readable 00:00:53.630 --> 00:00:53.640 align:start position:0% typed language that is easily readable 00:00:53.640 --> 00:00:57.110 align:start position:0% typed language that is easily readable for<00:00:54.270> web<00:00:55.020> developers<00:00:55.560> or<00:00:55.860> for<00:00:56.120> not 00:00:57.110 --> 00:00:57.120 align:start position:0% for web developers or for not 00:00:57.120 --> 00:00:59.660 align:start position:0% for web developers or for not necessarily<00:00:57.570> rapid<00:00:57.810> wellas<00:00:58.050> but<00:00:58.260> for<00:00:58.500> I<00:00:58.770> don't 00:00:59.660 --> 00:00:59.670 align:start position:0% necessarily rapid wellas but for I don't 00:00:59.670 --> 00:01:06.200 align:start position:0% necessarily rapid wellas but for I don't know<00:00:59.820> casual<00:01:00.390> programmers<00:01:02.390> so<00:01:04.460> yeah<00:01:05.460> we<00:01:05.640> we 00:01:06.200 --> 00:01:06.210 align:start position:0% know casual programmers so yeah we we 00:01:06.210 --> 00:01:08.510 align:start position:0% know casual programmers so yeah we we chose<00:01:06.630> something<00:01:07.530> that<00:01:07.649> looks<00:01:07.920> like<00:01:08.460> a 00:01:08.510 --> 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very very efficient<00:01:24.630> because<00:01:24.840> there's<00:01:25.439> not<00:01:25.740> a<00:01:25.799> lot<00:01:26.100> we 00:01:26.120 --> 00:01:26.130 align:start position:0% efficient because there's not a lot we 00:01:26.130 --> 00:01:29.239 align:start position:0% efficient because there's not a lot we can<00:01:26.429> do<00:01:26.639> inside<00:01:27.270> a<00:01:27.689> single<00:01:28.679> block<00:01:28.889> at<00:01:29.069> least 00:01:29.239 --> 00:01:29.249 align:start position:0% can do inside a single block at least 00:01:29.249 --> 00:01:33.469 align:start position:0% can do inside a single block at least currently<00:01:29.729> and<00:01:31.459> yeah<00:01:32.459> keep<00:01:32.880> that<00:01:33.060> it<00:01:33.270> keep 00:01:33.469 --> 00:01:33.479 align:start position:0% currently and yeah keep that it keep 00:01:33.479 --> 00:01:36.889 align:start position:0% currently and yeah keep that it keep that<00:01:33.630> in<00:01:33.749> mind<00:01:33.929> because<00:01:34.549> sometimes<00:01:35.749> yes<00:01:36.749> a 00:01:36.889 --> 00:01:36.899 align:start position:0% that in mind because sometimes yes a 00:01:36.899 --> 00:01:38.300 align:start position:0% that in mind because sometimes yes a little<00:01:37.109> she<00:01:37.229> looks<00:01:37.439> really<00:01:37.950> really<00:01:38.189> high 00:01:38.300 --> 00:01:38.310 align:start position:0% little she looks really really high 00:01:38.310 --> 00:01:40.819 align:start position:0% little she looks really really high level<00:01:38.490> but<00:01:39.020> actually<00:01:40.020> it's<00:01:40.139> not<00:01:40.289> that<00:01:40.350> far 00:01:40.819 --> 00:01:40.829 align:start position:0% level but actually it's not that far 00:01:40.829 --> 00:01:46.279 align:start position:0% level but actually it's not that far away<00:01:41.009> from<00:01:41.240> assembly<00:01:44.509> okay<00:01:45.509> what<00:01:45.990> happened 00:01:46.279 --> 00:01:46.289 align:start position:0% away from assembly okay what happened 00:01:46.289 --> 00:01:50.510 align:start position:0% away from assembly okay what happened since<00:01:46.590> DEFCON<00:01:47.130> 1<00:01:47.959> we<00:01:48.959> extended<00:01:49.619> solidity<00:01:50.100> to 00:01:50.510 --> 00:01:50.520 align:start position:0% since DEFCON 1 we extended solidity to 00:01:50.520 --> 00:01:56.929 align:start position:0% since DEFCON 1 we extended solidity to be<00:01:50.670> more<00:01:51.209> flexible<00:01:51.709> more<00:01:54.799> usable<00:01:55.799> so<00:01:56.189> we<00:01:56.789> added 00:01:56.929 --> 00:01:56.939 align:start position:0% be more flexible more usable so we added 00:01:56.939 --> 00:02:00.169 align:start position:0% be more flexible more usable so we added some<00:01:57.060> some<00:01:57.450> usability<00:01:57.749> features<00:01:58.079> and<00:01:59.090> not<00:02:00.090> to 00:02:00.169 --> 00:02:00.179 align:start position:0% some some usability features and not to 00:02:00.179 --> 00:02:03.230 align:start position:0% some some usability features and not to forget<00:02:00.329> we<00:02:00.840> made<00:02:01.109> it<00:02:01.399> safer<00:02:02.399> at<00:02:02.670> least<00:02:02.939> I<00:02:03.090> hope 00:02:03.230 --> 00:02:03.240 align:start position:0% forget we made it safer at least I hope 00:02:03.240 --> 00:02:09.650 align:start position:0% forget we made it safer at least I hope so<00:02:03.709> so<00:02:04.709> what<00:02:04.920> exactly<00:02:05.009> did<00:02:05.340> we<00:02:05.399> do<00:02:08.599> next<00:02:09.599> slide 00:02:09.650 --> 00:02:09.660 align:start position:0% so so what exactly did we do next slide 00:02:09.660 --> 00:02:14.780 align:start position:0% so so what exactly did we do next slide please<00:02:12.260> it's<00:02:13.260> now<00:02:13.560> possible<00:02:13.830> to<00:02:14.099> build<00:02:14.250> custom 00:02:14.780 --> 00:02:14.790 align:start position:0% please it's now possible to build custom 00:02:14.790 --> 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already<00:02:26.159> but<00:02:26.340> we<00:02:26.579> added<00:02:27.260> so<00:02:28.260> called 00:02:28.460 --> 00:02:28.470 align:start position:0% one already but we added so called 00:02:28.470 --> 00:02:28.970 align:start position:0% one already but we added so called intern 00:02:28.970 --> 00:02:28.980 align:start position:0% intern 00:02:28.980 --> 00:02:31.820 align:start position:0% intern library<00:02:29.459> functions<00:02:29.909> and<00:02:30.319> not<00:02:31.319> to<00:02:31.409> forget<00:02:31.530> the 00:02:31.820 --> 00:02:31.830 align:start position:0% library functions and not to forget the 00:02:31.830 --> 00:02:33.740 align:start position:0% library functions and not to forget the using<00:02:32.159> X<00:02:32.310> for<00:02:32.580> y<00:02:32.760> so<00:02:33.030> let's<00:02:33.360> look<00:02:33.540> at<00:02:33.659> an 00:02:33.740 --> 00:02:33.750 align:start position:0% using X for y so let's look at an 00:02:33.750 --> 00:02:38.420 align:start position:0% using X for y so let's look at an example<00:02:34.849> this<00:02:35.849> is<00:02:35.989> I<00:02:36.989> think<00:02:37.470> Nick<00:02:37.920> Johnson 00:02:38.420 --> 00:02:38.430 align:start position:0% example this is I think Nick Johnson 00:02:38.430 --> 00:02:41.210 align:start position:0% example this is I think Nick Johnson string<00:02:39.420> library<00:02:39.659> at<00:02:40.110> least<00:02:40.290> a<00:02:40.500> small<00:02:40.860> fragment 00:02:41.210 --> 00:02:41.220 align:start position:0% string library at least a small fragment 00:02:41.220 --> 00:02:45.979 align:start position:0% string library at least a small fragment of<00:02:41.489> it<00:02:41.640> and<00:02:43.129> it<00:02:44.330> inside<00:02:45.330> this<00:02:45.450> library<00:02:45.840> you 00:02:45.979 --> 00:02:45.989 align:start position:0% of it and it inside this library you 00:02:45.989 --> 00:02:49.460 align:start position:0% of it and it inside this library you have<00:02:46.019> this<00:02:46.379> struct<00:02:47.040> slice<00:02:47.720> which<00:02:48.720> defines<00:02:49.349> a 00:02:49.460 --> 00:02:49.470 align:start position:0% have this struct slice which defines a 00:02:49.470 --> 00:02:53.080 align:start position:0% have this struct slice which defines a new<00:02:49.590> type<00:02:49.830> and<00:02:50.129> it's<00:02:50.849> basically<00:02:51.060> a<00:02:51.540> a<00:02:52.080> view<00:02:52.739> on 00:02:53.080 --> 00:02:53.090 align:start position:0% new type and it's basically a a view on 00:02:53.090 --> 00:02:56.930 align:start position:0% new type and it's basically a a view on memory<00:02:54.090> it<00:02:54.750> has<00:02:55.140> a<00:02:55.319> pointer<00:02:55.920> which<00:02:56.250> is<00:02:56.430> so<00:02:56.670> it's 00:02:56.930 --> 00:02:56.940 align:start position:0% memory it has a pointer which is so it's 00:02:56.940 --> 00:02:59.149 align:start position:0% memory it has a pointer which is so it's a<00:02:57.030> kind<00:02:57.209> of<00:02:57.269> rather<00:02:58.079> low<00:02:58.290> level<00:02:58.560> object<00:02:58.920> it<00:02:59.040> has 00:02:59.149 --> 00:02:59.159 align:start position:0% a kind of rather low level object it has 00:02:59.159 --> 00:03:00.949 align:start position:0% a kind of rather low level object it has a<00:02:59.190> pointer<00:02:59.610> and<00:02:59.760> a<00:02:59.819> length<00:02:59.970> so<00:03:00.269> it<00:03:00.299> references 00:03:00.949 --> 00:03:00.959 align:start position:0% a pointer and a length so it references 00:03:00.959 --> 00:03:04.910 align:start position:0% a pointer and a length so it references a<00:03:01.200> chunk<00:03:02.160> of<00:03:02.310> memory<00:03:02.459> and<00:03:03.019> the<00:03:04.019> function<00:03:04.680> to 00:03:04.910 --> 00:03:04.920 align:start position:0% a chunk of memory and the function to 00:03:04.920 --> 00:03:08.259 align:start position:0% a chunk of memory and the function to slice<00:03:05.190> can<00:03:05.579> be<00:03:05.670> called<00:03:05.940> on<00:03:06.150> any<00:03:06.269> string<00:03:06.660> and<00:03:06.840> it 00:03:08.259 --> 00:03:08.269 align:start position:0% slice can be called on any string and it 00:03:08.269 --> 00:03:11.300 align:start position:0% slice can be called on any string and it creates<00:03:09.319> such<00:03:10.319> a<00:03:10.349> slice<00:03:10.680> object<00:03:11.220> that 00:03:11.300 --> 00:03:11.310 align:start position:0% creates such a slice object that 00:03:11.310 --> 00:03:15.170 align:start position:0% creates such a slice object that references<00:03:11.970> the<00:03:12.030> data<00:03:12.359> of<00:03:12.599> that<00:03:12.810> string<00:03:14.180> that 00:03:15.170 --> 00:03:15.180 align:start position:0% references the data of that string that 00:03:15.180 --> 00:03:19.449 align:start position:0% references the data of that string that is<00:03:15.239> important<00:03:15.750> because<00:03:15.900> usually<00:03:16.379> when<00:03:16.769> you 00:03:19.449 --> 00:03:19.459 align:start position:0% 00:03:19.459 --> 00:03:26.449 align:start position:0% when<00:03:20.459> you<00:03:23.120> create<00:03:24.120> so<00:03:24.739> we<00:03:25.739> want<00:03:25.920> to<00:03:26.010> be<00:03:26.099> able<00:03:26.220> to 00:03:26.449 --> 00:03:26.459 align:start position:0% when you create so we want to be able to 00:03:26.459 --> 00:03:28.759 align:start position:0% when you create so we want to be able to reference<00:03:26.700> parts<00:03:27.450> of<00:03:27.660> strings<00:03:27.989> and<00:03:28.319> if<00:03:28.470> we<00:03:28.590> use 00:03:28.759 --> 00:03:28.769 align:start position:0% reference parts of strings and if we use 00:03:28.769 --> 00:03:30.619 align:start position:0% reference parts of strings and if we use just<00:03:29.160> the<00:03:29.400> string<00:03:29.760> type<00:03:29.940> itself<00:03:30.269> we<00:03:30.510> would 00:03:30.619 --> 00:03:30.629 align:start position:0% just the string type itself we would 00:03:30.629 --> 00:03:32.869 align:start position:0% just the string type itself we would have<00:03:30.780> to<00:03:30.900> copy<00:03:31.109> it<00:03:31.290> all<00:03:31.410> the<00:03:31.530> time<00:03:31.560> and<00:03:31.950> using 00:03:32.869 --> 00:03:32.879 align:start position:0% have to copy it all the time and using 00:03:32.879 --> 00:03:35.300 align:start position:0% have to copy it all the time and using this<00:03:33.090> slice<00:03:33.389> we<00:03:33.690> can<00:03:33.930> talk<00:03:34.290> about<00:03:34.470> parts<00:03:35.190> of 00:03:35.300 --> 00:03:35.310 align:start position:0% this slice we can talk about parts of 00:03:35.310 --> 00:03:39.710 align:start position:0% this slice we can talk about parts of strings<00:03:35.579> and<00:03:36.139> let's<00:03:37.639> so<00:03:38.639> at<00:03:38.910> the<00:03:39.329> bottom<00:03:39.599> we 00:03:39.710 --> 00:03:39.720 align:start position:0% strings and let's so at the bottom we 00:03:39.720 --> 00:03:41.890 align:start position:0% strings and let's so at the bottom we have<00:03:39.750> a<00:03:39.870> contract<00:03:40.109> that<00:03:40.230> actually<00:03:40.620> uses<00:03:40.769> this 00:03:41.890 --> 00:03:41.900 align:start position:0% have a contract that actually uses this 00:03:41.900 --> 00:03:46.250 align:start position:0% have a contract that actually uses this slice<00:03:43.430> it<00:03:44.430> takes<00:03:44.700> a<00:03:44.819> string<00:03:45.060> it<00:03:45.720> calls<00:03:45.989> to 00:03:46.250 --> 00:03:46.260 align:start position:0% slice it takes a string it calls to 00:03:46.260 --> 00:03:47.780 align:start position:0% slice it takes a string it calls to slice<00:03:46.500> which<00:03:46.769> converts<00:03:47.099> it<00:03:47.250> to<00:03:47.280> such<00:03:47.489> a<00:03:47.519> slice 00:03:47.780 --> 00:03:47.790 align:start position:0% slice which converts it to such a slice 00:03:47.790 --> 00:03:51.229 align:start position:0% slice which converts it to such a slice and<00:03:48.060> then<00:03:48.599> checks<00:03:49.500> whether<00:03:49.739> it<00:03:50.220> starts<00:03:50.790> with 00:03:51.229 --> 00:03:51.239 align:start position:0% and then checks whether it starts with 00:03:51.239 --> 00:03:55.220 align:start position:0% and then checks whether it starts with foo<00:03:51.810> so<00:03:52.109> it<00:03:53.209> checks<00:03:54.209> whether<00:03:54.359> the<00:03:54.540> prefix<00:03:54.989> is 00:03:55.220 --> 00:03:55.230 align:start position:0% foo so it checks whether the prefix is 00:03:55.230 --> 00:04:01.039 align:start position:0% foo so it checks whether the prefix is foo<00:03:55.440> and<00:03:56.989> no<00:03:57.989> not<00:03:58.139> yet<00:03:58.430> so<00:03:59.430> and<00:03:59.840> the<00:04:00.840> great 00:04:01.039 --> 00:04:01.049 align:start position:0% foo and no not yet so and the great 00:04:01.049 --> 00:04:03.770 align:start position:0% foo and no not yet so and the great thing<00:04:01.079> is<00:04:01.290> that<00:04:01.410> you<00:04:01.769> can<00:04:02.060> so<00:04:03.060> using<00:04:03.690> this 00:04:03.770 --> 00:04:03.780 align:start position:0% thing is that you can so using this 00:04:03.780 --> 00:04:06.860 align:start position:0% thing is that you can so using this using<00:04:04.440> strings<00:04:04.799> for<00:04:05.130> star<00:04:05.430> statement<00:04:06.329> you<00:04:06.840> can 00:04:06.860 --> 00:04:06.870 align:start position:0% using strings for star statement you can 00:04:06.870 --> 00:04:10.460 align:start position:0% using strings for star statement you can basically<00:04:07.230> attached<00:04:08.840> functions<00:04:09.840> from<00:04:10.380> a 00:04:10.460 --> 00:04:10.470 align:start position:0% basically attached functions from a 00:04:10.470 --> 00:04:13.250 align:start position:0% basically attached functions from a library<00:04:10.950> to<00:04:11.280> an<00:04:11.430> existing<00:04:11.700> type<00:04:12.150> and<00:04:12.389> that's 00:04:13.250 --> 00:04:13.260 align:start position:0% library to an existing type and that's 00:04:13.260 --> 00:04:15.979 align:start position:0% library to an existing type and that's why<00:04:13.530> we<00:04:13.709> can<00:04:13.889> call<00:04:14.069> s<00:04:14.340> dot<00:04:14.639> to<00:04:14.879> slice<00:04:15.180> although 00:04:15.979 --> 00:04:15.989 align:start position:0% why we can call s dot to slice although 00:04:15.989 --> 00:04:20.000 align:start position:0% why we can call s dot to slice although s<00:04:16.229> is<00:04:16.530> a<00:04:16.729> built-in<00:04:17.900> type<00:04:18.900> that<00:04:19.139> usually<00:04:19.530> that 00:04:20.000 --> 00:04:20.010 align:start position:0% s is a built-in type that usually that 00:04:20.010 --> 00:04:21.170 align:start position:0% s is a built-in type that usually that that<00:04:20.160> of<00:04:20.250> course<00:04:20.400> does<00:04:20.579> not<00:04:20.609> have<00:04:21.000> the 00:04:21.170 --> 00:04:21.180 align:start position:0% that of course does not have the 00:04:21.180 --> 00:04:23.990 align:start position:0% that of course does not have the function<00:04:21.539> to<00:04:21.660> slice<00:04:21.930> and<00:04:22.310> I<00:04:23.310> think<00:04:23.760> this<00:04:23.820> is<00:04:23.880> a 00:04:23.990 --> 00:04:24.000 align:start position:0% function to slice and I think this is a 00:04:24.000 --> 00:04:27.529 align:start position:0% function to slice and I think this is a really<00:04:24.210> powerful<00:04:24.930> tool<00:04:26.060> especially<00:04:27.060> when 00:04:27.529 --> 00:04:27.539 align:start position:0% really powerful tool especially when 00:04:27.539 --> 00:04:29.240 align:start position:0% really powerful tool especially when coupled<00:04:27.750> with<00:04:27.960> inline<00:04:28.320> assembly<00:04:28.800> because<00:04:28.919> you 00:04:29.240 --> 00:04:29.250 align:start position:0% coupled with inline assembly because you 00:04:29.250 --> 00:04:33.800 align:start position:0% coupled with inline assembly because you can<00:04:30.139> create<00:04:31.139> tools<00:04:31.910> using<00:04:32.910> inline<00:04:33.180> assembly 00:04:33.800 --> 00:04:33.810 align:start position:0% can create tools using inline assembly 00:04:33.810 --> 00:04:35.900 align:start position:0% can create tools using inline assembly without<00:04:34.320> having<00:04:34.860> to<00:04:34.949> change<00:04:35.220> the<00:04:35.400> compilers 00:04:35.900 --> 00:04:35.910 align:start position:0% without having to change the compilers 00:04:35.910 --> 00:04:38.570 align:start position:0% without having to change the compilers you<00:04:36.090> can<00:04:36.300> basically<00:04:36.990> add<00:04:37.320> types<00:04:37.950> that<00:04:38.340> look 00:04:38.570 --> 00:04:38.580 align:start position:0% you can basically add types that look 00:04:38.580 --> 00:04:41.209 align:start position:0% you can basically add types that look like<00:04:38.789> built-in<00:04:39.330> types<00:04:39.630> but<00:04:40.469> you<00:04:40.710> do<00:04:40.830> not<00:04:40.950> have 00:04:41.209 --> 00:04:41.219 align:start position:0% like built-in types but you do not have 00:04:41.219 --> 00:04:43.100 align:start position:0% like built-in types but you do not have to<00:04:41.729> take<00:04:41.940> do 00:04:43.100 --> 00:04:43.110 align:start position:0% to take do 00:04:43.110 --> 00:04:48.080 align:start position:0% to take do have<00:04:43.320> to<00:04:43.470> look<00:04:43.620> into<00:04:43.770> the<00:04:43.950> compiler<00:04:46.760> okay<00:04:47.760> what 00:04:48.080 --> 00:04:48.090 align:start position:0% have to look into the compiler okay what 00:04:48.090 --> 00:04:54.260 align:start position:0% have to look into the compiler okay what we<00:04:48.210> also<00:04:48.360> did<00:04:48.690> is<00:04:49.520> we<00:04:50.520> so<00:04:51.330> we<00:04:52.670> extended<00:04:53.670> the<00:04:53.790> AST 00:04:54.260 --> 00:04:54.270 align:start position:0% we also did is we so we extended the AST 00:04:54.270 --> 00:04:57.740 align:start position:0% we also did is we so we extended the AST output<00:04:54.720> capabilities<00:04:55.050> and<00:04:56.360> one<00:04:57.360> of<00:04:57.450> the<00:04:57.540> goals 00:04:57.740 --> 00:04:57.750 align:start position:0% output capabilities and one of the goals 00:04:57.750 --> 00:05:01.880 align:start position:0% output capabilities and one of the goals there<00:04:58.110> is<00:04:58.350> to<00:04:58.680> provide<00:04:59.370> more<00:05:00.740> make<00:05:01.740> the 00:05:01.880 --> 00:05:01.890 align:start position:0% there is to provide more make the 00:05:01.890 --> 00:05:04.130 align:start position:0% there is to provide more make the compiler<00:05:02.370> more<00:05:02.760> accessible<00:05:03.360> to<00:05:03.390> external 00:05:04.130 --> 00:05:04.140 align:start position:0% compiler more accessible to external 00:05:04.140 --> 00:05:06.890 align:start position:0% compiler more accessible to external tools<00:05:04.350> which<00:05:04.830> want<00:05:05.340> to<00:05:05.460> do<00:05:05.640> static<00:05:06.390> analysis 00:05:06.890 --> 00:05:06.900 align:start position:0% tools which want to do static analysis 00:05:06.900 --> 00:05:12.440 align:start position:0% tools which want to do static analysis or<00:05:07.110> debugging<00:05:07.710> and<00:05:09.350> so<00:05:10.350> this<00:05:10.620> is<00:05:10.850> still<00:05:11.850> a<00:05:12.240> bit 00:05:12.440 --> 00:05:12.450 align:start position:0% or debugging and so this is still a bit 00:05:12.450 --> 00:05:15.290 align:start position:0% or debugging and so this is still a bit fluid<00:05:13.050> so<00:05:13.350> we<00:05:13.530> might<00:05:13.770> change<00:05:14.100> the<00:05:14.490> we<00:05:15.090> might 00:05:15.290 --> 00:05:15.300 align:start position:0% fluid so we might change the we might 00:05:15.300 --> 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statement return x + y and this gets converted<00:05:26.970> into<00:05:27.210> the<00:05:27.450> to<00:05:27.660> the<00:05:27.750> following<00:05:28.020> json 00:05:28.460 --> 00:05:28.470 align:start position:0% converted into the to the following json 00:05:28.470 --> 00:05:31.490 align:start position:0% converted into the to the following json a<00:05:28.710> representation<00:05:29.520> of<00:05:29.580> the<00:05:29.730> ast<00:05:30.120> ast<00:05:30.320> we<00:05:31.320> have 00:05:31.490 --> 00:05:31.500 align:start position:0% a representation of the ast ast we have 00:05:31.500 --> 00:05:36.260 align:start position:0% a representation of the ast ast we have an<00:05:31.620> ID<00:05:32.930> which<00:05:33.930> is<00:05:34.370> used<00:05:35.370> to<00:05:35.610> reference<00:05:35.790> other 00:05:36.260 --> 00:05:36.270 align:start position:0% an ID which is used to reference other 00:05:36.270 --> 00:05:39.170 align:start position:0% an ID which is used to reference other nodes<00:05:36.570> in<00:05:36.780> the<00:05:36.900> ASCO<00:05:37.260> perhaps<00:05:37.770> I<00:05:37.860> took<00:05:38.430> a<00:05:38.610> STS 00:05:39.170 --> 00:05:39.180 align:start position:0% nodes in the ASCO perhaps I took a STS 00:05:39.180 --> 00:05:41.540 align:start position:0% nodes in the ASCO perhaps I took a STS then<00:05:39.420> is<00:05:39.750> short<00:05:40.050> for<00:05:40.080> abstract<00:05:40.920> syntax<00:05:41.100> tree 00:05:41.540 --> 00:05:41.550 align:start position:0% then is short for abstract syntax tree 00:05:41.550 --> 00:05:45.350 align:start position:0% then is short for abstract syntax tree and<00:05:41.840> that<00:05:42.840> is<00:05:42.960> basically<00:05:43.350> a<00:05:44.360> representation 00:05:45.350 --> 00:05:45.360 align:start position:0% and that is basically a representation 00:05:45.360 --> 00:05:48.080 align:start position:0% and that is basically a representation of<00:05:45.480> a<00:05:45.930> structured<00:05:46.650> representation<00:05:47.490> of<00:05:47.610> the 00:05:48.080 --> 00:05:48.090 align:start position:0% of a structured representation of the 00:05:48.090 --> 00:05:52.520 align:start position:0% of a structured representation of the source<00:05:48.330> code<00:05:48.540> of<00:05:48.720> a<00:05:48.780> program<00:05:49.820> and<00:05:51.410> so<00:05:52.410> this 00:05:52.520 --> 00:05:52.530 align:start position:0% source code of a program and so this 00:05:52.530 --> 00:05:54.560 align:start position:0% source code of a program and so this return<00:05:52.980> X<00:05:53.190> plus<00:05:53.400> y<00:05:53.610> is<00:05:53.640> decomposed<00:05:54.090> in<00:05:54.480> the 00:05:54.560 --> 00:05:54.570 align:start position:0% return X plus y is decomposed in the 00:05:54.570 --> 00:05:57.110 align:start position:0% return X plus y is decomposed in the return<00:05:55.080> statement<00:05:55.320> and<00:05:55.770> then<00:05:56.400> inside<00:05:56.940> this 00:05:57.110 --> 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to<00:06:16.200> the<00:06:16.530> actual<00:06:16.890> position<00:06:17.370> in<00:06:17.520> the<00:06:17.640> source 00:06:17.840 --> 00:06:17.850 align:start position:0% to the actual position in the source 00:06:17.850 --> 00:06:20.630 align:start position:0% to the actual position in the source code<00:06:18.090> where<00:06:18.420> this<00:06:18.680> this<00:06:19.680> piece<00:06:20.010> of<00:06:20.160> the<00:06:20.280> AST 00:06:20.630 --> 00:06:20.640 align:start position:0% code where this this piece of the AST 00:06:20.640 --> 00:06:24.200 align:start position:0% code where this this piece of the AST came<00:06:20.850> from<00:06:21.090> and<00:06:21.300> that<00:06:22.490> is<00:06:23.490> very<00:06:23.640> important<00:06:24.030> for 00:06:24.200 --> 00:06:24.210 align:start position:0% came from and that is very important for 00:06:24.210 --> 00:06:27.770 align:start position:0% came from and that is very important for further<00:06:24.480> bugger<00:06:24.810> because<00:06:25.680> at<00:06:26.610> any<00:06:27.330> point<00:06:27.600> in 00:06:27.770 --> 00:06:27.780 align:start position:0% further bugger because at any point in 00:06:27.780 --> 00:06:33.400 align:start position:0% further bugger because at any point in the<00:06:27.840> code<00:06:28.140> it<00:06:28.410> can<00:06:28.590> show<00:06:28.830> you<00:06:28.890> so<00:06:31.100> if<00:06:32.150> your 00:06:33.400 --> 00:06:33.410 align:start position:0% the code it can show you so if your 00:06:33.410 --> 00:06:36.110 align:start position:0% the code it can show you so if your debugger<00:06:34.410> transaction<00:06:34.980> then<00:06:35.130> you<00:06:35.280> can<00:06:35.490> at<00:06:36.030> any 00:06:36.110 --> 00:06:36.120 align:start position:0% debugger transaction then you can at any 00:06:36.120 --> 00:06:38.240 align:start position:0% debugger transaction then you can at any point<00:06:36.500> inside<00:06:37.500> the<00:06:37.650> execution<00:06:38.100> of<00:06:38.130> the 00:06:38.240 --> 00:06:38.250 align:start position:0% point inside the execution of the 00:06:38.250 --> 00:06:41.150 align:start position:0% point inside the execution of the transaction<00:06:38.670> you<00:06:38.760> know<00:06:39.050> where<00:06:40.050> that<00:06:40.470> was 00:06:41.150 --> 00:06:41.160 align:start position:0% transaction you know where that was 00:06:41.160 --> 00:06:42.830 align:start position:0% transaction you know where that was where<00:06:41.850> you<00:06:41.940> currently<00:06:42.060> are<00:06:42.270> in<00:06:42.390> the<00:06:42.630> source 00:06:42.830 --> 00:06:42.840 align:start position:0% where you currently are in the source 00:06:42.840 --> 00:06:47.210 align:start position:0% where you currently are in the source code<00:06:42.990> and<00:06:44.600> you<00:06:45.600> can<00:06:45.630> also<00:06:45.870> do<00:06:46.140> more<00:06:46.680> analysis 00:06:47.210 --> 00:06:47.220 align:start position:0% code and you can also do more analysis 00:06:47.220 --> 00:06:52.240 align:start position:0% code and you can also do more analysis on<00:06:47.490> the<00:06:47.640> ast<00:06:48.060> and<00:06:48.090> perhaps<00:06:48.810> so<00:06:49.320> perhaps 00:06:52.240 --> 00:06:52.250 align:start position:0% 00:06:52.250 --> 00:06:55.980 align:start position:0% analyze<00:06:53.250> the<00:06:53.400> AST<00:06:53.760> for<00:06:54.120> insecure<00:06:55.050> stuff 00:06:55.980 --> 00:06:55.990 align:start position:0% analyze the AST for insecure stuff 00:06:55.990 --> 00:06:58.380 align:start position:0% analyze the AST for insecure stuff and<00:06:56.100> notify<00:06:57.100> the<00:06:57.160> user<00:06:57.310> and<00:06:57.790> point<00:06:58.120> to<00:06:58.300> an 00:06:58.380 --> 00:06:58.390 align:start position:0% and notify the user and point to an 00:06:58.390 --> 00:07:00.630 align:start position:0% and notify the user and point to an exact<00:06:58.690> location<00:06:58.750> in<00:06:59.200> the<00:06:59.320> source<00:06:59.530> where<00:06:59.830> this 00:07:00.630 --> 00:07:00.640 align:start position:0% exact location in the source where this 00:07:00.640 --> 00:07:07.560 align:start position:0% exact location in the source where this problem<00:07:01.030> is<00:07:04.590> yeah<00:07:05.590> concerning<00:07:06.040> safety<00:07:06.570> we 00:07:07.560 --> 00:07:07.570 align:start position:0% problem is yeah concerning safety we 00:07:07.570 --> 00:07:09.360 align:start position:0% problem is yeah concerning safety we already<00:07:07.750> had<00:07:08.050> several<00:07:08.500> talks<00:07:08.830> about<00:07:09.070> formal 00:07:09.360 --> 00:07:09.370 align:start position:0% already had several talks about formal 00:07:09.370 --> 00:07:11.400 align:start position:0% already had several talks about formal verification<00:07:09.490> so<00:07:10.060> I<00:07:10.120> won't<00:07:10.780> say<00:07:11.230> anything 00:07:11.400 --> 00:07:11.410 align:start position:0% verification so I won't say anything 00:07:11.410 --> 00:07:16.380 align:start position:0% verification so I won't say anything about<00:07:11.560> that<00:07:12.270> with<00:07:13.270> the<00:07:14.580> 040<00:07:15.580> release<00:07:16.060> of 00:07:16.380 --> 00:07:16.390 align:start position:0% about that with the 040 release of 00:07:16.390 --> 00:07:19.440 align:start position:0% about that with the 040 release of solidity<00:07:16.750> we<00:07:17.110> added<00:07:17.380> some<00:07:18.180> changes<00:07:19.180> that 00:07:19.440 --> 00:07:19.450 align:start position:0% solidity we added some changes that 00:07:19.450 --> 00:07:21.180 align:start position:0% solidity we added some changes that intentionally<00:07:20.350> broke<00:07:20.680> backwards 00:07:21.180 --> 00:07:21.190 align:start position:0% intentionally broke backwards 00:07:21.190 --> 00:07:23.520 align:start position:0% intentionally broke backwards compatibility<00:07:21.850> in<00:07:22.120> order<00:07:22.450> to<00:07:22.630> add<00:07:22.990> some 00:07:23.520 --> 00:07:23.530 align:start position:0% compatibility in order to add some 00:07:23.530 --> 00:07:26.880 align:start position:0% compatibility in order to add some safety<00:07:23.920> features<00:07:24.430> and<00:07:25.560> some<00:07:26.560> of<00:07:26.680> them<00:07:26.860> were 00:07:26.880 --> 00:07:26.890 align:start position:0% safety features and some of them were 00:07:26.890 --> 00:07:32.910 align:start position:0% safety features and some of them were that<00:07:27.580> we<00:07:28.740> created<00:07:29.740> exceptions<00:07:30.780> for<00:07:31.780> in<00:07:32.290> more 00:07:32.910 --> 00:07:32.920 align:start position:0% that we created exceptions for in more 00:07:32.920 --> 00:07:35.970 align:start position:0% that we created exceptions for in more situations<00:07:33.190> than<00:07:33.730> before<00:07:33.880> and<00:07:34.620> the<00:07:35.620> effect<00:07:35.890> of 00:07:35.970 --> 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position:0% the transaction so whenever you encounter<00:07:46.630> a<00:07:49.170> yeah<00:07:50.700> troublesome<00:07:51.700> situation 00:07:51.900 --> 00:07:51.910 align:start position:0% encounter a yeah troublesome situation 00:07:51.910 --> 00:07:54.840 align:start position:0% encounter a yeah troublesome situation or<00:07:52.630> some<00:07:52.960> situation<00:07:53.500> where<00:07:54.160> it's<00:07:54.280> not<00:07:54.460> really 00:07:54.840 --> 00:07:54.850 align:start position:0% or some situation where it's not really 00:07:54.850 --> 00:07:58.560 align:start position:0% or some situation where it's not really clear<00:07:55.180> what<00:07:55.360> to<00:07:55.780> do<00:07:55.930> how<00:07:56.320> to<00:07:56.350> deal<00:07:56.590> with<00:07:56.770> it<00:07:57.570> at 00:07:58.560 --> 00:07:58.570 align:start position:0% clear what to do how to deal with it at 00:07:58.570 --> 00:08:02.210 align:start position:0% clear what to do how to deal with it at least<00:07:59.140> not<00:07:59.350> for<00:07:59.830> the<00:07:59.950> compiler<00:08:00.310> then<00:08:01.210> this 00:08:02.210 --> 00:08:02.220 align:start position:0% least not for the compiler then this 00:08:02.220 --> 00:08:05.310 align:start position:0% least not for the compiler then this basically<00:08:03.220> undo<00:08:04.180> the<00:08:04.660> effect<00:08:05.020> of<00:08:05.170> the 00:08:05.310 --> 00:08:05.320 align:start position:0% basically undo the effect of the 00:08:05.320 --> 00:08:07.200 align:start position:0% basically undo the effect of the transaction<00:08:05.860> this<00:08:06.370> is<00:08:06.550> this<00:08:06.790> can<00:08:07.180> be 00:08:07.200 --> 00:08:07.210 align:start position:0% transaction this is this can be 00:08:07.210 --> 00:08:09.840 align:start position:0% transaction this is this can be dangerous<00:08:07.510> in<00:08:07.900> some<00:08:08.110> situations<00:08:08.740> it's<00:08:09.340> so 00:08:09.840 --> 00:08:09.850 align:start position:0% dangerous in some situations it's so 00:08:09.850 --> 00:08:13.470 align:start position:0% dangerous in some situations it's so especially<00:08:10.660> when<00:08:11.110> you<00:08:11.320> for<00:08:12.250> example<00:08:12.450> have<00:08:13.450> a 00:08:13.470 --> 00:08:13.480 align:start position:0% especially when you for example have a 00:08:13.480 --> 00:08:16.980 align:start position:0% especially when you for example have a loop<00:08:13.780> and<00:08:14.080> one<00:08:15.010> of<00:08:15.160> the<00:08:15.460> eight<00:08:16.210> arrests<00:08:16.630> inside 00:08:16.980 --> 00:08:16.990 align:start position:0% loop and one of the eight arrests inside 00:08:16.990 --> 00:08:18.720 align:start position:0% loop and one of the eight arrests inside the<00:08:17.140> loop<00:08:17.290> always<00:08:17.890> triggers<00:08:18.190> an<00:08:18.310> exception 00:08:18.720 --> 00:08:18.730 align:start position:0% the loop always triggers an exception 00:08:18.730 --> 00:08:20.310 align:start position:0% the loop always triggers an exception then<00:08:18.880> it's<00:08:19.000> impossible<00:08:19.660> for<00:08:19.690> the<00:08:19.900> loop<00:08:20.020> to<00:08:20.200> go 00:08:20.310 --> 00:08:20.320 align:start position:0% then it's impossible for the loop to go 00:08:20.320 --> 00:08:22.350 align:start position:0% then it's impossible for the loop to go through<00:08:20.560> so<00:08:20.740> this<00:08:21.130> is<00:08:21.280> something<00:08:21.460> to<00:08:21.730> be<00:08:22.270> aware 00:08:22.350 --> 00:08:22.360 align:start position:0% through so this is something to be aware 00:08:22.360 --> 00:08:27.300 align:start position:0% through so this is something to be aware of<00:08:22.540> but<00:08:23.530> we<00:08:24.100> chose<00:08:24.400> to<00:08:24.430> rather<00:08:26.160> revert<00:08:27.160> the 00:08:27.300 --> 00:08:27.310 align:start position:0% of but we chose to rather revert the 00:08:27.310 --> 00:08:29.780 align:start position:0% of but we chose to rather revert the transaction<00:08:27.820> than<00:08:28.060> so<00:08:28.810> yeah<00:08:29.200> we<00:08:29.320> chose<00:08:29.530> to 00:08:29.780 --> 00:08:29.790 align:start position:0% transaction than so yeah we chose to 00:08:29.790 --> 00:08:33.780 align:start position:0% transaction than so yeah we chose to reverting<00:08:30.790> a<00:08:30.850> transaction<00:08:31.420> is<00:08:32.580> less<00:08:33.580> of<00:08:33.730> a 00:08:33.780 --> 00:08:33.790 align:start position:0% reverting a transaction is less of a 00:08:33.790 --> 00:08:37.940 align:start position:0% reverting a transaction is less of a problem<00:08:33.970> than<00:08:34.210> getting<00:08:34.780> stuck<00:08:34.960> and<00:08:36.090> so<00:08:37.090> yeah 00:08:37.940 --> 00:08:37.950 align:start position:0% problem than getting stuck and so yeah 00:08:37.950 --> 00:08:40.710 align:start position:0% problem than getting stuck and so yeah failed<00:08:38.950> creations<00:08:39.520> now<00:08:40.180> throw<00:08:40.510> an<00:08:40.600> exception 00:08:40.710 --> 00:08:40.720 align:start position:0% failed creations now throw an exception 00:08:40.720 --> 00:08:43.940 align:start position:0% failed creations now throw an exception division<00:08:41.530> by<00:08:41.650> zero<00:08:41.890> throws<00:08:42.160> an<00:08:42.280> exception<00:08:42.370> and 00:08:43.940 --> 00:08:43.950 align:start position:0% division by zero throws an exception and 00:08:43.950 --> 00:08:46.830 align:start position:0% division by zero throws an exception and yeah<00:08:44.950> function<00:08:45.520> calls<00:08:45.760> to<00:08:46.000> a<00:08:46.030> non-contract 00:08:46.830 --> 00:08:46.840 align:start position:0% yeah function calls to a non-contract 00:08:46.840 --> 00:08:50.600 align:start position:0% yeah function calls to a non-contract this<00:08:46.990> function<00:08:47.440> calls<00:08:47.650> to<00:08:47.800> a<00:08:47.830> non-contract<00:08:48.370> is 00:08:50.600 --> 00:08:50.610 align:start position:0% 00:08:50.610 --> 00:08:53.520 align:start position:0% especially<00:08:51.610> important<00:08:52.060> because<00:08:52.120> if<00:08:52.600> if<00:08:53.050> you 00:08:53.520 --> 00:08:53.530 align:start position:0% especially important because if if you 00:08:53.530 --> 00:08:59.250 align:start position:0% especially important because if if you call<00:08:53.710> a<00:08:53.740> non-contract<00:08:54.990> it<00:08:55.990> will<00:08:56.350> basically<00:08:58.260> if 00:08:59.250 --> 00:08:59.260 align:start position:0% call a non-contract it will basically if 00:08:59.260 --> 00:09:01.290 align:start position:0% call a non-contract it will basically if you<00:08:59.740> send<00:08:59.950> other<00:09:00.130> together<00:09:00.790> with<00:09:00.970> it<00:09:01.090> it<00:09:01.210> will 00:09:01.290 --> 00:09:01.300 align:start position:0% you send other together with it it will 00:09:01.300 --> 00:09:03.210 align:start position:0% you send other together with it it will just<00:09:01.480> accept<00:09:01.750> it<00:09:01.930> and<00:09:02.050> it<00:09:02.290> might<00:09:02.800> be<00:09:02.830> forever 00:09:03.210 --> 00:09:03.220 align:start position:0% just accept it and it might be forever 00:09:03.220 --> 00:09:06.060 align:start position:0% just accept it and it might be forever stuck<00:09:03.310> there<00:09:03.730> and<00:09:04.200> then<00:09:05.200> we<00:09:05.320> have<00:09:05.590> the<00:09:05.860> the 00:09:06.060 --> 00:09:06.070 align:start position:0% stuck there and then we have the the 00:09:06.070 --> 00:09:07.740 align:start position:0% stuck there and then we have the the payable<00:09:06.430> modifier<00:09:06.820> so<00:09:07.090> you<00:09:07.150> now<00:09:07.450> have<00:09:07.480> to 00:09:07.740 --> 00:09:07.750 align:start position:0% payable modifier so you now have to 00:09:07.750 --> 00:09:09.810 align:start position:0% payable modifier so you now have to explicitly<00:09:08.640> specify 00:09:09.810 --> 00:09:09.820 align:start position:0% explicitly specify 00:09:09.820 --> 00:09:11.490 align:start position:0% explicitly specify for<00:09:09.940> every<00:09:10.180> function<00:09:10.600> whether<00:09:10.840> it<00:09:11.080> is<00:09:11.200> allowed 00:09:11.490 --> 00:09:11.500 align:start position:0% for every function whether it is allowed 00:09:11.500 --> 00:09:14.370 align:start position:0% for every function whether it is allowed to<00:09:11.710> receive<00:09:11.860> other<00:09:12.250> and<00:09:12.580> the<00:09:13.330> default<00:09:13.750> is<00:09:13.990> to 00:09:14.370 --> 00:09:14.380 align:start position:0% to receive other and the default is to 00:09:14.380 --> 00:09:18.360 align:start position:0% to receive other and the default is to reject<00:09:14.920> other<00:09:15.370> so<00:09:16.800> it's<00:09:17.800> harder<00:09:18.340> to 00:09:18.360 --> 00:09:18.370 align:start position:0% reject other so it's harder to 00:09:18.370 --> 00:09:23.570 align:start position:0% reject other so it's harder to accidentally<00:09:19.360> send<00:09:20.520> send<00:09:21.520> fun<00:09:21.730> somewhere<00:09:21.970> and 00:09:23.570 --> 00:09:23.580 align:start position:0% accidentally send send fun somewhere and 00:09:23.580 --> 00:09:26.760 align:start position:0% accidentally send send fun somewhere and to<00:09:24.580> make<00:09:24.730> the<00:09:24.910> the<00:09:25.420> version<00:09:25.840> transition<00:09:26.230> safer 00:09:26.760 --> 00:09:26.770 align:start position:0% to make the the version transition safer 00:09:26.770 --> 00:09:29.790 align:start position:0% to make the the version transition safer we<00:09:27.190> also<00:09:27.340> added<00:09:27.580> the<00:09:27.760> version<00:09:28.060> pragma<00:09:28.800> which 00:09:29.790 --> 00:09:29.800 align:start position:0% we also added the version pragma which 00:09:29.800 --> 00:09:32.040 align:start position:0% we also added the version pragma which means<00:09:30.070> you<00:09:30.190> can<00:09:30.340> now<00:09:30.460> specify<00:09:30.790> the<00:09:31.660> compiler 00:09:32.040 --> 00:09:32.050 align:start position:0% means you can now specify the compiler 00:09:32.050 --> 00:09:35.220 align:start position:0% means you can now specify the compiler version<00:09:32.170> your<00:09:33.040> source<00:09:33.700> code<00:09:33.850> is<00:09:34.240> designed<00:09:35.020> to 00:09:35.220 --> 00:09:35.230 align:start position:0% version your source code is designed to 00:09:35.230 --> 00:09:39.030 align:start position:0% version your source code is designed to work<00:09:35.260> with<00:09:35.620> and<00:09:35.890> if<00:09:36.790> we<00:09:37.390> if<00:09:38.290> we<00:09:38.470> change<00:09:38.830> the 00:09:39.030 --> 00:09:39.040 align:start position:0% work with and if we if we change the 00:09:39.040 --> 00:09:40.440 align:start position:0% work with and if we if we change the compiler<00:09:39.370> if<00:09:39.580> we<00:09:39.670> change<00:09:39.880> the<00:09:40.000> language<00:09:40.150> in 00:09:40.440 --> 00:09:40.450 align:start position:0% compiler if we change the language in 00:09:40.450 --> 00:09:43.220 align:start position:0% compiler if we change the language in the<00:09:40.540> future<00:09:40.900> then<00:09:41.410> this<00:09:41.650> version<00:09:42.220> pragma<00:09:42.640> will 00:09:43.220 --> 00:09:43.230 align:start position:0% the future then this version pragma will 00:09:43.230 --> 00:09:45.660 align:start position:0% the future then this version pragma will tell<00:09:44.230> the<00:09:44.380> developer<00:09:44.860> yeah<00:09:45.160> there<00:09:45.490> might<00:09:45.610> be 00:09:45.660 --> 00:09:45.670 align:start position:0% tell the developer yeah there might be 00:09:45.670 --> 00:09:48.150 align:start position:0% tell the developer yeah there might be some<00:09:45.940> changes<00:09:46.330> so<00:09:46.630> you<00:09:47.170> probably<00:09:47.860> have<00:09:48.100> to 00:09:48.150 --> 00:09:48.160 align:start position:0% some changes so you probably have to 00:09:48.160 --> 00:09:49.250 align:start position:0% some changes so you probably have to take<00:09:48.370> a<00:09:48.400> look<00:09:48.580> at<00:09:48.670> the<00:09:48.730> source<00:09:48.940> code<00:09:49.030> and 00:09:49.250 --> 00:09:49.260 align:start position:0% take a look at the source code and 00:09:49.260 --> 00:09:54.870 align:start position:0% take a look at the source code and modified<00:09:50.260> accordingly<00:09:50.710> and<00:09:51.960> then<00:09:52.960> some<00:09:53.880> we 00:09:54.870 --> 00:09:54.880 align:start position:0% modified accordingly and then some we 00:09:54.880 --> 00:09:59.790 align:start position:0% modified accordingly and then some we also<00:09:55.000> fix<00:09:55.510> the<00:09:55.660> problem<00:09:56.110> with<00:09:56.230> modifiers<00:09:58.800> so 00:09:59.790 --> 00:09:59.800 align:start position:0% also fix the problem with modifiers so 00:09:59.800 --> 00:10:02.880 align:start position:0% also fix the problem with modifiers so modifiers<00:10:00.370> are<00:10:00.990> kind<00:10:01.990> of<00:10:02.050> properties<00:10:02.740> you<00:10:02.860> can 00:10:02.880 --> 00:10:02.890 align:start position:0% modifiers are kind of properties you can 00:10:02.890 --> 00:10:04.620 align:start position:0% modifiers are kind of properties you can attach<00:10:03.250> two<00:10:03.490> functions<00:10:03.910> which<00:10:04.180> insert<00:10:04.600> a 00:10:04.620 --> 00:10:04.630 align:start position:0% attach two functions which insert a 00:10:04.630 --> 00:10:07.860 align:start position:0% attach two functions which insert a prefix<00:10:05.200> and<00:10:05.470> suffix<00:10:06.210> into<00:10:07.210> the<00:10:07.330> function<00:10:07.510> and 00:10:07.860 --> 00:10:07.870 align:start position:0% prefix and suffix into the function and 00:10:07.870 --> 00:10:11.460 align:start position:0% prefix and suffix into the function and this<00:10:08.590> underscore<00:10:09.430> part<00:10:09.850> there<00:10:10.420> is<00:10:10.720> where<00:10:11.320> the 00:10:11.460 --> 00:10:11.470 align:start position:0% this underscore part there is where the 00:10:11.470 --> 00:10:13.280 align:start position:0% this underscore part there is where the actual<00:10:11.770> function<00:10:12.130> is<00:10:12.220> inserted<00:10:12.670> and 00:10:13.280 --> 00:10:13.290 align:start position:0% actual function is inserted and 00:10:13.290 --> 00:10:16.350 align:start position:0% actual function is inserted and previously<00:10:14.290> if<00:10:14.620> we<00:10:14.740> hadn't<00:10:15.070> previously<00:10:16.030> it 00:10:16.350 --> 00:10:16.360 align:start position:0% previously if we hadn't previously it 00:10:16.360 --> 00:10:19.470 align:start position:0% previously if we hadn't previously it was<00:10:16.450> more<00:10:16.870> syntax<00:10:17.650> based<00:10:17.920> which<00:10:18.670> means<00:10:18.940> if<00:10:19.180> the 00:10:19.470 --> 00:10:19.480 align:start position:0% was more syntax based which means if the 00:10:19.480 --> 00:10:22.760 align:start position:0% was more syntax based which means if the function<00:10:19.780> had<00:10:20.050> a<00:10:20.080> return<00:10:20.530> it<00:10:20.890> actually 00:10:22.760 --> 00:10:22.770 align:start position:0% function had a return it actually 00:10:22.770 --> 00:10:25.680 align:start position:0% function had a return it actually returned<00:10:23.770> and<00:10:24.130> in<00:10:24.580> the<00:10:24.940> sense<00:10:25.180> that<00:10:25.300> it<00:10:25.540> also 00:10:25.680 --> 00:10:25.690 align:start position:0% returned and in the sense that it also 00:10:25.690 --> 00:10:28.080 align:start position:0% returned and in the sense that it also skipped<00:10:26.170> the<00:10:26.710> trailing<00:10:27.370> partea<00:10:27.760> so<00:10:27.940> this 00:10:28.080 --> 00:10:28.090 align:start position:0% skipped the trailing partea so this 00:10:28.090 --> 00:10:30.630 align:start position:0% skipped the trailing partea so this locked<00:10:28.420> equals<00:10:28.870> false<00:10:29.370> would<00:10:30.370> have<00:10:30.460> been 00:10:30.630 --> 00:10:30.640 align:start position:0% locked equals false would have been 00:10:30.640 --> 00:10:32.460 align:start position:0% locked equals false would have been skipped<00:10:30.940> before<00:10:31.120> with<00:10:31.720> a<00:10:31.750> return<00:10:32.110> but<00:10:32.380> it 00:10:32.460 --> 00:10:32.470 align:start position:0% skipped before with a return but it 00:10:32.470 --> 00:10:34.430 align:start position:0% skipped before with a return but it would<00:10:32.590> not<00:10:32.740> have<00:10:32.920> been<00:10:32.950> skipped<00:10:33.400> if<00:10:33.520> you<00:10:33.610> just 00:10:34.430 --> 00:10:34.440 align:start position:0% would not have been skipped if you just 00:10:34.440 --> 00:10:37.880 align:start position:0% would not have been skipped if you just completed<00:10:35.440> the<00:10:35.590> function<00:10:36.040> and<00:10:36.390> this<00:10:37.390> now 00:10:37.880 --> 00:10:37.890 align:start position:0% completed the function and this now 00:10:37.890 --> 00:10:41.120 align:start position:0% completed the function and this now hopefully<00:10:38.890> makes<00:10:39.100> it<00:10:39.280> possible<00:10:39.460> to<00:10:39.810> create 00:10:41.120 --> 00:10:41.130 align:start position:0% hopefully makes it possible to create 00:10:41.130 --> 00:10:46.530 align:start position:0% hopefully makes it possible to create mutexes<00:10:42.810> which<00:10:44.190> allow<00:10:45.190> a<00:10:45.220> function<00:10:45.790> to<00:10:46.510> be 00:10:46.530 --> 00:10:46.540 align:start position:0% mutexes which allow a function to be 00:10:46.540 --> 00:10:50.810 align:start position:0% mutexes which allow a function to be active<00:10:46.990> only<00:10:47.380> once<00:10:47.620> in<00:10:47.890> that<00:10:48.850> there<00:10:49.210> is<00:10:49.240> a 00:10:50.810 --> 00:10:50.820 align:start position:0% active only once in that there is a 00:10:50.820 --> 00:10:53.580 align:start position:0% active only once in that there is a variable<00:10:51.820> and<00:10:52.000> storage<00:10:52.420> called<00:10:53.110> locked<00:10:53.410> in 00:10:53.580 --> 00:10:53.590 align:start position:0% variable and storage called locked in 00:10:53.590 --> 00:10:55.680 align:start position:0% variable and storage called locked in this<00:10:53.710> example<00:10:54.100> and<00:10:54.430> if<00:10:55.090> the<00:10:55.240> function<00:10:55.390> is 00:10:55.680 --> 00:10:55.690 align:start position:0% this example and if the function is 00:10:55.690 --> 00:10:57.690 align:start position:0% this example and if the function is active<00:10:56.410> its<00:10:56.620> set<00:10:56.800> it<00:10:56.920> true<00:10:57.130> and<00:10:57.370> it's 00:10:57.690 --> 00:10:57.700 align:start position:0% active its set it true and it's 00:10:57.700 --> 00:10:59.880 align:start position:0% active its set it true and it's automatically<00:10:58.450> set<00:10:58.870> to<00:10:58.900> falls<00:10:59.290> again<00:10:59.650> if<00:10:59.800> the 00:10:59.880 --> 00:10:59.890 align:start position:0% automatically set to falls again if the 00:10:59.890 --> 00:11:05.460 align:start position:0% automatically set to falls again if the function<00:11:00.070> exits<00:11:00.550> and<00:11:00.780> if<00:11:02.550> if<00:11:03.810> the<00:11:04.810> function<00:11:05.260> is 00:11:05.460 --> 00:11:05.470 align:start position:0% function exits and if if the function is 00:11:05.470 --> 00:11:07.410 align:start position:0% function exits and if if the function is locked<00:11:05.740> then<00:11:06.040> you<00:11:06.460> cannot<00:11:06.730> call<00:11:06.910> it<00:11:07.090> so<00:11:07.240> this 00:11:07.410 --> 00:11:07.420 align:start position:0% locked then you cannot call it so this 00:11:07.420 --> 00:11:13.100 align:start position:0% locked then you cannot call it so this yeah<00:11:10.860> right 00:11:13.100 --> 00:11:13.110 align:start position:0% yeah right 00:11:13.110 --> 00:11:15.920 align:start position:0% yeah right okay<00:11:14.040> how<00:11:14.160> does<00:11:14.220> the<00:11:14.370> future<00:11:14.490> look<00:11:14.930> again 00:11:15.920 --> 00:11:15.930 align:start position:0% okay how does the future look again 00:11:15.930 --> 00:11:20.449 align:start position:0% okay how does the future look again formal<00:11:16.260> verification<00:11:17.810> then<00:11:18.810> one<00:11:19.410> important<00:11:20.339> a 00:11:20.449 --> 00:11:20.459 align:start position:0% formal verification then one important a 00:11:20.459 --> 00:11:24.319 align:start position:0% formal verification then one important a large<00:11:20.670> feature<00:11:20.940> we<00:11:21.420> will<00:11:21.570> add<00:11:21.720> is<00:11:23.269> something<00:11:24.269> i 00:11:24.319 --> 00:11:24.329 align:start position:0% large feature we will add is something i 00:11:24.329 --> 00:11:26.569 align:start position:0% large feature we will add is something i call<00:11:24.510> authenticated<00:11:25.350> sources<00:11:25.890> and<00:11:26.040> binaries 00:11:26.569 --> 00:11:26.579 align:start position:0% call authenticated sources and binaries 00:11:26.579 --> 00:11:29.900 align:start position:0% call authenticated sources and binaries this<00:11:27.480> means<00:11:27.779> that<00:11:27.950> we<00:11:28.950> that<00:11:29.399> the<00:11:29.550> compiler 00:11:29.900 --> 00:11:29.910 align:start position:0% this means that we that the compiler 00:11:29.910 --> 00:11:33.410 align:start position:0% this means that we that the compiler will<00:11:30.149> automatically<00:11:30.899> insert<00:11:31.470> a<00:11:31.709> hash<00:11:32.579> of<00:11:32.880> the 00:11:33.410 --> 00:11:33.420 align:start position:0% will automatically insert a hash of the 00:11:33.420 --> 00:11:38.870 align:start position:0% will automatically insert a hash of the metadata<00:11:33.990> into<00:11:34.380> the<00:11:34.709> bytecode<00:11:35.810> and<00:11:37.880> using 00:11:38.870 --> 00:11:38.880 align:start position:0% metadata into the bytecode and using 00:11:38.880 --> 00:11:40.819 align:start position:0% metadata into the bytecode and using this<00:11:39.000> hash<00:11:39.269> you<00:11:39.510> can<00:11:39.690> retrieve<00:11:40.140> the<00:11:40.440> metadata 00:11:40.819 --> 00:11:40.829 align:start position:0% this hash you can retrieve the metadata 00:11:40.829 --> 00:11:47.389 align:start position:0% this hash you can retrieve the metadata from<00:11:41.070> swarm<00:11:43.250> that<00:11:44.250> means<00:11:44.610> that<00:11:46.190> so<00:11:47.190> the 00:11:47.389 --> 00:11:47.399 align:start position:0% from swarm that means that so the 00:11:47.399 --> 00:11:49.100 align:start position:0% from swarm that means that so the metadata<00:11:47.730> will<00:11:48.060> contain<00:11:48.480> a<00:11:48.720> lot<00:11:48.930> of 00:11:49.100 --> 00:11:49.110 align:start position:0% metadata will contain a lot of 00:11:49.110 --> 00:11:52.130 align:start position:0% metadata will contain a lot of information<00:11:49.680> about<00:11:49.769> the<00:11:50.070> contract<00:11:51.140> this 00:11:52.130 --> 00:11:52.140 align:start position:0% information about the contract this 00:11:52.140 --> 00:11:54.980 align:start position:0% information about the contract this includes<00:11:52.529> the<00:11:52.680> ABI<00:11:52.950> interface<00:11:53.519> and<00:11:53.990> the 00:11:54.980 --> 00:11:54.990 align:start position:0% includes the ABI interface and the 00:11:54.990 --> 00:11:58.550 align:start position:0% includes the ABI interface and the effect<00:11:55.829> of<00:11:55.950> that<00:11:56.010> is<00:11:56.160> if<00:11:56.760> you<00:11:57.180> load<00:11:57.750> up<00:11:57.959> a<00:11:58.140> smart 00:11:58.550 --> 00:11:58.560 align:start position:0% effect of that is if you load up a smart 00:11:58.560 --> 00:12:00.290 align:start position:0% effect of that is if you load up a smart contract<00:11:58.950> inside<00:11:59.279> mist<00:11:59.550> and<00:11:59.790> want<00:12:00.209> to 00:12:00.290 --> 00:12:00.300 align:start position:0% contract inside mist and want to 00:12:00.300 --> 00:12:02.660 align:start position:0% contract inside mist and want to interact<00:12:00.510> with<00:12:00.839> it<00:12:00.959> you<00:12:01.440> do<00:12:01.589> not<00:12:01.620> have<00:12:01.980> to<00:12:02.250> copy 00:12:02.660 --> 00:12:02.670 align:start position:0% interact with it you do not have to copy 00:12:02.670 --> 00:12:04.370 align:start position:0% interact with it you do not have to copy and<00:12:02.910> paste<00:12:03.120> the<00:12:03.329> ABI<00:12:03.600> anymore<00:12:04.110> it<00:12:04.260> will 00:12:04.370 --> 00:12:04.380 align:start position:0% and paste the ABI anymore it will 00:12:04.380 --> 00:12:05.930 align:start position:0% and paste the ABI anymore it will automatically<00:12:04.829> retrieve<00:12:05.190> it<00:12:05.310> from<00:12:05.430> swarm<00:12:05.760> and 00:12:05.930 --> 00:12:05.940 align:start position:0% automatically retrieve it from swarm and 00:12:05.940 --> 00:12:08.199 align:start position:0% automatically retrieve it from swarm and it's<00:12:06.540> also<00:12:06.720> authenticated<00:12:07.620> in<00:12:07.680> the<00:12:07.740> way<00:12:07.890> that 00:12:08.199 --> 00:12:08.209 align:start position:0% it's also authenticated in the way that 00:12:08.209 --> 00:12:11.660 align:start position:0% it's also authenticated in the way that that<00:12:09.209> is<00:12:09.360> the<00:12:09.510> ABI<00:12:09.810> the<00:12:10.649> programmer<00:12:11.190> intended 00:12:11.660 --> 00:12:11.670 align:start position:0% that is the ABI the programmer intended 00:12:11.670 --> 00:12:13.220 align:start position:0% that is the ABI the programmer intended to<00:12:11.760> prove<00:12:11.940> the<00:12:12.269> smart<00:12:12.540> contract<00:12:12.839> you<00:12:12.930> have<00:12:12.959> so 00:12:13.220 --> 00:12:13.230 align:start position:0% to prove the smart contract you have so 00:12:13.230 --> 00:12:16.030 align:start position:0% to prove the smart contract you have so you<00:12:13.320> can't<00:12:13.589> make<00:12:13.769> any<00:12:13.950> copy<00:12:14.490> paste<00:12:14.760> arrows<00:12:15.600> and 00:12:16.030 --> 00:12:16.040 align:start position:0% you can't make any copy paste arrows and 00:12:16.040 --> 00:12:19.220 align:start position:0% you can't make any copy paste arrows and it<00:12:17.040> will<00:12:17.190> also<00:12:17.550> have<00:12:17.730> a<00:12:17.970> link<00:12:18.540> to<00:12:18.870> the<00:12:18.990> source 00:12:19.220 --> 00:12:19.230 align:start position:0% it will also have a link to the source 00:12:19.230 --> 00:12:21.650 align:start position:0% it will also have a link to the source code<00:12:19.560> and<00:12:19.800> link<00:12:20.550> in<00:12:20.699> the<00:12:20.790> sense<00:12:21.000> of<00:12:21.180> link<00:12:21.480> to 00:12:21.650 --> 00:12:21.660 align:start position:0% code and link in the sense of link to 00:12:21.660 --> 00:12:23.480 align:start position:0% code and link in the sense of link to swarm<00:12:22.050> of<00:12:22.230> course<00:12:22.589> which<00:12:22.890> means<00:12:23.130> that<00:12:23.220> it's 00:12:23.480 --> 00:12:23.490 align:start position:0% swarm of course which means that it's 00:12:23.490 --> 00:12:25.100 align:start position:0% swarm of course which means that it's it's<00:12:23.790> the<00:12:24.510> source<00:12:24.690> code<00:12:24.839> is<00:12:24.959> hash 00:12:25.100 --> 00:12:25.110 align:start position:0% it's the source code is hash 00:12:25.110 --> 00:12:28.310 align:start position:0% it's the source code is hash authenticated<00:12:25.890> and<00:12:26.040> this<00:12:26.630> hash<00:12:27.630> is<00:12:27.899> part<00:12:28.199> of 00:12:28.310 --> 00:12:28.320 align:start position:0% authenticated and this hash is part of 00:12:28.320 --> 00:12:30.889 align:start position:0% authenticated and this hash is part of the<00:12:28.470> bytecode<00:12:28.649> so<00:12:29.610> it's<00:12:30.000> the<00:12:30.269> exact<00:12:30.630> source 00:12:30.889 --> 00:12:30.899 align:start position:0% the bytecode so it's the exact source 00:12:30.899 --> 00:12:33.350 align:start position:0% the bytecode so it's the exact source code<00:12:31.170> of<00:12:31.410> the<00:12:31.470> the<00:12:32.010> programmer<00:12:32.399> used<00:12:33.060> when 00:12:33.350 --> 00:12:33.360 align:start position:0% code of the the programmer used when 00:12:33.360 --> 00:12:36.079 align:start position:0% code of the the programmer used when compiling<00:12:33.690> a<00:12:33.839> smart<00:12:34.079> contract<00:12:34.500> and<00:12:34.910> it<00:12:35.910> will 00:12:36.079 --> 00:12:36.089 align:start position:0% compiling a smart contract and it will 00:12:36.089 --> 00:12:39.079 align:start position:0% compiling a smart contract and it will also<00:12:36.810> have<00:12:37.019> the<00:12:37.380> the<00:12:37.740> compiler<00:12:38.070> version<00:12:38.160> which 00:12:39.079 --> 00:12:39.089 align:start position:0% also have the the compiler version which 00:12:39.089 --> 00:12:41.120 align:start position:0% also have the the compiler version which means<00:12:39.329> mist<00:12:39.839> can<00:12:40.110> automatically<00:12:40.769> achieve 00:12:41.120 --> 00:12:41.130 align:start position:0% means mist can automatically achieve 00:12:41.130 --> 00:12:43.340 align:start position:0% means mist can automatically achieve both<00:12:41.550> the<00:12:41.820> ABI<00:12:42.149> interface<00:12:42.690> and<00:12:42.899> the<00:12:43.140> source 00:12:43.340 --> 00:12:43.350 align:start position:0% both the ABI interface and the source 00:12:43.350 --> 00:12:46.639 align:start position:0% both the ABI interface and the source code<00:12:43.620> and<00:12:44.240> the<00:12:45.240> compiler<00:12:45.959> with<00:12:46.260> the<00:12:46.380> correct 00:12:46.639 --> 00:12:46.649 align:start position:0% code and the compiler with the correct 00:12:46.649 --> 00:12:48.829 align:start position:0% code and the compiler with the correct version<00:12:47.149> compile<00:12:48.149> the<00:12:48.329> source<00:12:48.360> code<00:12:48.810> and 00:12:48.829 --> 00:12:48.839 align:start position:0% version compile the source code and 00:12:48.839 --> 00:12:50.840 align:start position:0% version compile the source code and verify<00:12:49.470> that<00:12:49.829> this<00:12:49.949> is<00:12:50.100> actually<00:12:50.519> the<00:12:50.640> source 00:12:50.840 --> 00:12:50.850 align:start position:0% verify that this is actually the source 00:12:50.850 --> 00:12:52.970 align:start position:0% verify that this is actually the source code<00:12:51.060> and<00:12:51.209> then<00:12:51.779> show<00:12:52.320> the<00:12:52.589> source<00:12:52.800> code 00:12:52.970 --> 00:12:52.980 align:start position:0% code and then show the source code 00:12:52.980 --> 00:12:58.460 align:start position:0% code and then show the source code documentation<00:12:53.160> to<00:12:53.910> the<00:12:54.000> user<00:12:56.390> yeah<00:12:57.390> and<00:12:57.570> since 00:12:58.460 --> 00:12:58.470 align:start position:0% documentation to the user yeah and since 00:12:58.470 --> 00:13:01.220 align:start position:0% documentation to the user yeah and since the<00:12:58.829> the<00:12:59.190> form<00:13:00.089> of<00:13:00.209> verification<00:13:00.269> conditions 00:13:01.220 --> 00:13:01.230 align:start position:0% the the form of verification conditions 00:13:01.230 --> 00:13:03.130 align:start position:0% the the form of verification conditions are<00:13:01.410> part<00:13:01.649> of<00:13:01.709> the<00:13:01.829> source<00:13:02.070> code<00:13:02.250> it<00:13:02.399> can<00:13:02.550> even 00:13:03.130 --> 00:13:03.140 align:start position:0% are part of the source code it can even 00:13:03.140 --> 00:13:06.530 align:start position:0% are part of the source code it can even automatically<00:13:04.140> do<00:13:04.610> just<00:13:05.610> in<00:13:05.760> time<00:13:05.970> former 00:13:06.530 --> 00:13:06.540 align:start position:0% automatically do just in time former 00:13:06.540 --> 00:13:10.519 align:start position:0% automatically do just in time former verification<00:13:07.079> of<00:13:07.140> the<00:13:07.230> small<00:13:07.470> contract<00:13:09.529> ok 00:13:10.519 --> 00:13:10.529 align:start position:0% verification of the small contract ok 00:13:10.529 --> 00:13:12.829 align:start position:0% verification of the small contract ok then<00:13:11.180> templates<00:13:12.180> is<00:13:12.329> something<00:13:12.630> we<00:13:12.720> would 00:13:12.829 --> 00:13:12.839 align:start position:0% then templates is something we would 00:13:12.839 --> 00:13:15.530 align:start position:0% then templates is something we would like<00:13:12.959> to<00:13:13.079> add<00:13:13.199> so<00:13:13.970> this<00:13:14.970> is<00:13:15.000> sometimes<00:13:15.360> called 00:13:15.530 --> 00:13:15.540 align:start position:0% like to add so this is sometimes called 00:13:15.540 --> 00:13:18.370 align:start position:0% like to add so this is sometimes called generic<00:13:16.320> data<00:13:16.680> structures<00:13:17.310> or<00:13:17.519> generics<00:13:18.029> and 00:13:18.370 --> 00:13:18.380 align:start position:0% generic data structures or generics and 00:13:18.380 --> 00:13:21.410 align:start position:0% generic data structures or generics and I<00:13:19.380> hope<00:13:19.949> that<00:13:20.190> it<00:13:20.399> will<00:13:20.640> also<00:13:21.180> increase 00:13:21.410 --> 00:13:21.420 align:start position:0% I hope that it will also increase 00:13:21.420 --> 00:13:24.380 align:start position:0% I hope that it will also increase flexibility<00:13:22.170> because<00:13:22.500> you<00:13:22.920> can<00:13:23.390> implement 00:13:24.380 --> 00:13:24.390 align:start position:0% flexibility because you can implement 00:13:24.390 --> 00:13:26.450 align:start position:0% flexibility because you can implement one<00:13:24.750> tree<00:13:25.020> one<00:13:25.440> routine 00:13:26.450 --> 00:13:26.460 align:start position:0% one tree one routine 00:13:26.460 --> 00:13:28.160 align:start position:0% one tree one routine one<00:13:26.550> algorithm<00:13:26.820> once<00:13:27.270> and<00:13:27.570> then<00:13:27.660> reuse<00:13:27.990> it<00:13:28.140> for 00:13:28.160 --> 00:13:28.170 align:start position:0% one algorithm once and then reuse it for 00:13:28.170 --> 00:13:31.310 align:start position:0% one algorithm once and then reuse it for multiple<00:13:28.650> data<00:13:28.800> types<00:13:29.870> we<00:13:30.870> will<00:13:30.990> also<00:13:31.110> add 00:13:31.310 --> 00:13:31.320 align:start position:0% multiple data types we will also add 00:13:31.320 --> 00:13:33.080 align:start position:0% multiple data types we will also add functions<00:13:31.860> as<00:13:31.980> first-class<00:13:32.310> citizens<00:13:32.910> this 00:13:33.080 --> 00:13:33.090 align:start position:0% functions as first-class citizens this 00:13:33.090 --> 00:13:36.680 align:start position:0% functions as first-class citizens this means<00:13:33.390> you<00:13:33.900> can<00:13:33.930> have<00:13:34.320> things<00:13:34.980> like<00:13:35.690> anonymous 00:13:36.680 --> 00:13:36.690 align:start position:0% means you can have things like anonymous 00:13:36.690 --> 00:13:39.710 align:start position:0% means you can have things like anonymous functions<00:13:37.110> lambda<00:13:37.530> functions<00:13:37.920> and<00:13:38.420> use<00:13:39.420> them 00:13:39.710 --> 00:13:39.720 align:start position:0% functions lambda functions and use them 00:13:39.720 --> 00:13:43.490 align:start position:0% functions lambda functions and use them as<00:13:40.020> for<00:13:40.860> example<00:13:41.220> as<00:13:41.310> callbacks<00:13:41.820> in<00:13:42.500> Oracle 00:13:43.490 --> 00:13:43.500 align:start position:0% as for example as callbacks in Oracle 00:13:43.500 --> 00:13:47.060 align:start position:0% as for example as callbacks in Oracle queries<00:13:43.860> so<00:13:44.130> currently<00:13:45.120> oracle<00:13:46.080> eyes<00:13:46.170> uses 00:13:47.060 --> 00:13:47.070 align:start position:0% queries so currently oracle eyes uses 00:13:47.070 --> 00:13:54.770 align:start position:0% queries so currently oracle eyes uses some<00:13:47.310> kind<00:13:47.550> of<00:13:47.990> yeah<00:13:53.120> manual<00:13:54.120> solution<00:13:54.660> to 00:13:54.770 --> 00:13:54.780 align:start position:0% some kind of yeah manual solution to 00:13:54.780 --> 00:13:57.470 align:start position:0% some kind of yeah manual solution to that<00:13:54.870> problem<00:13:54.930> because<00:13:55.730> if<00:13:56.730> you<00:13:56.970> if<00:13:57.270> you<00:13:57.450> make 00:13:57.470 --> 00:13:57.480 align:start position:0% that problem because if you if you make 00:13:57.480 --> 00:14:00.020 align:start position:0% that problem because if you if you make a<00:13:57.630> request<00:13:57.900> to<00:13:58.080> oracle<00:13:58.470> eyes<00:13:58.560> then<00:13:58.950> the<00:13:59.370> oracle 00:14:00.020 --> 00:14:00.030 align:start position:0% a request to oracle eyes then the oracle 00:14:00.030 --> 00:14:03.680 align:start position:0% a request to oracle eyes then the oracle i<00:14:00.090> smart<00:14:00.480> contract<00:14:02.120> invokes<00:14:03.120> the<00:14:03.300> arclight 00:14:03.680 --> 00:14:03.690 align:start position:0% i smart contract invokes the arclight 00:14:03.690 --> 00:14:06.260 align:start position:0% i smart contract invokes the arclight system<00:14:04.110> and<00:14:04.380> retrieves<00:14:04.800> the<00:14:05.010> data<00:14:05.040> and<00:14:05.550> then 00:14:06.260 --> 00:14:06.270 align:start position:0% system and retrieves the data and then 00:14:06.270 --> 00:14:10.490 align:start position:0% system and retrieves the data and then calls<00:14:07.430> calls<00:14:08.430> back<00:14:08.730> the<00:14:09.570> original<00:14:09.810> contract 00:14:10.490 --> 00:14:10.500 align:start position:0% calls calls back the original contract 00:14:10.500 --> 00:14:14.270 align:start position:0% calls calls back the original contract in<00:14:10.680> a<00:14:11.130> later<00:14:12.000> transaction<00:14:12.720> and<00:14:13.280> currently 00:14:14.270 --> 00:14:14.280 align:start position:0% in a later transaction and currently 00:14:14.280 --> 00:14:16.070 align:start position:0% in a later transaction and currently this<00:14:14.730> call<00:14:14.970> that<00:14:15.150> goes<00:14:15.330> to<00:14:15.570> a<00:14:15.600> fixed<00:14:15.930> function 00:14:16.070 --> 00:14:16.080 align:start position:0% this call that goes to a fixed function 00:14:16.080 --> 00:14:18.770 align:start position:0% this call that goes to a fixed function with<00:14:16.350> a<00:14:16.380> fixed<00:14:16.560> name<00:14:16.890> but<00:14:17.760> in<00:14:18.150> the<00:14:18.360> future<00:14:18.540> will 00:14:18.770 --> 00:14:18.780 align:start position:0% with a fixed name but in the future will 00:14:18.780 --> 00:14:21.080 align:start position:0% with a fixed name but in the future will be<00:14:18.870> possible<00:14:19.230> to<00:14:19.320> just<00:14:19.470> supply<00:14:19.980> a<00:14:20.430> callback 00:14:21.080 --> 00:14:21.090 align:start position:0% be possible to just supply a callback 00:14:21.090 --> 00:14:22.910 align:start position:0% be possible to just supply a callback function<00:14:21.540> as<00:14:21.690> is<00:14:22.170> usual<00:14:22.560> in<00:14:22.590> asynchronous 00:14:22.910 --> 00:14:22.920 align:start position:0% function as is usual in asynchronous 00:14:22.920 --> 00:14:26.450 align:start position:0% function as is usual in asynchronous programming<00:14:23.190> and<00:14:24.950> yeah<00:14:25.950> speaking<00:14:26.250> of 00:14:26.450 --> 00:14:26.460 align:start position:0% programming and yeah speaking of 00:14:26.460 --> 00:14:29.840 align:start position:0% programming and yeah speaking of asynchronous<00:14:26.820> programming<00:14:28.610> not<00:14:29.610> sure<00:14:29.730> if 00:14:29.840 --> 00:14:29.850 align:start position:0% asynchronous programming not sure if 00:14:29.850 --> 00:14:33.680 align:start position:0% asynchronous programming not sure if you've<00:14:29.970> seen<00:14:30.210> this<00:14:31.970> proof-of-concept<00:14:32.970> hack 00:14:33.680 --> 00:14:33.690 align:start position:0% you've seen this proof-of-concept hack 00:14:33.690 --> 00:14:36.200 align:start position:0% you've seen this proof-of-concept hack two<00:14:34.440> weeks<00:14:34.620> ago<00:14:34.800> about<00:14:35.190> the<00:14:35.400> air<00:14:35.520> with<00:14:35.700> about 00:14:36.200 --> 00:14:36.210 align:start position:0% two weeks ago about the air with about 00:14:36.210 --> 00:14:45.860 align:start position:0% two weeks ago about the air with about the<00:14:36.330> await<00:14:39.080> way<00:14:40.080> to<00:14:40.140> program<00:14:40.830> so<00:14:44.270> yeah<00:14:45.270> we<00:14:45.510> in 00:14:45.860 --> 00:14:45.870 align:start position:0% the await way to program so yeah we in 00:14:45.870 --> 00:14:47.660 align:start position:0% the await way to program so yeah we in the<00:14:45.960> future<00:14:46.170> we<00:14:46.320> will<00:14:46.410> explore<00:14:46.950> no<00:14:47.160> new 00:14:47.660 --> 00:14:47.670 align:start position:0% the future we will explore no new 00:14:47.670 --> 00:14:49.610 align:start position:0% the future we will explore no new notations<00:14:48.300> for<00:14:48.390> how<00:14:48.780> to<00:14:48.840> you<00:14:49.050> how<00:14:49.350> to<00:14:49.410> do 00:14:49.610 --> 00:14:49.620 align:start position:0% notations for how to you how to do 00:14:49.620 --> 00:14:51.740 align:start position:0% notations for how to you how to do asynchronous<00:14:49.860> programming<00:14:50.250> because<00:14:50.750> often 00:14:51.740 --> 00:14:51.750 align:start position:0% asynchronous programming because often 00:14:51.750 --> 00:14:54.290 align:start position:0% asynchronous programming because often smart<00:14:52.380> contracts<00:14:52.860> are<00:14:53.040> a<00:14:53.070> sequence<00:14:53.700> consists 00:14:54.290 --> 00:14:54.300 align:start position:0% smart contracts are a sequence consists 00:14:54.300 --> 00:14:55.940 align:start position:0% smart contracts are a sequence consists of<00:14:54.390> a<00:14:54.510> sequence<00:14:54.720> of<00:14:54.990> things<00:14:55.230> to<00:14:55.410> be<00:14:55.530> done<00:14:55.680> in 00:14:55.940 --> 00:14:55.950 align:start position:0% of a sequence of things to be done in 00:14:55.950 --> 00:14:58.670 align:start position:0% of a sequence of things to be done in exactly<00:14:56.580> this<00:14:56.760> sequence<00:14:57.240> and<00:14:57.450> it<00:14:58.410> kind<00:14:58.620> of 00:14:58.670 --> 00:14:58.680 align:start position:0% exactly this sequence and it kind of 00:14:58.680 --> 00:15:01.690 align:start position:0% exactly this sequence and it kind of doesn't<00:14:59.130> really<00:14:59.490> make<00:14:59.640> sense<00:14:59.700> to<00:15:00.240> put<00:15:00.750> these 00:15:01.690 --> 00:15:01.700 align:start position:0% doesn't really make sense to put these 00:15:01.700 --> 00:15:03.890 align:start position:0% doesn't really make sense to put these different<00:15:02.700> steps<00:15:02.940> in<00:15:03.180> different<00:15:03.510> functions 00:15:03.890 --> 00:15:03.900 align:start position:0% different steps in different functions 00:15:03.900 --> 00:15:06.590 align:start position:0% different steps in different functions and<00:15:04.110> it's<00:15:04.260> much<00:15:04.590> easier<00:15:04.650> to<00:15:05.100> actually<00:15:05.600> program 00:15:06.590 --> 00:15:06.600 align:start position:0% and it's much easier to actually program 00:15:06.600 --> 00:15:09.080 align:start position:0% and it's much easier to actually program that<00:15:06.780> sequentially<00:15:07.580> that's<00:15:08.580> probably<00:15:08.850> hard 00:15:09.080 --> 00:15:09.090 align:start position:0% that sequentially that's probably hard 00:15:09.090 --> 00:15:10.760 align:start position:0% that sequentially that's probably hard to<00:15:09.120> explain<00:15:09.330> without<00:15:09.510> example<00:15:09.990> that's<00:15:10.140> okay 00:15:10.760 --> 00:15:10.770 align:start position:0% to explain without example that's okay 00:15:10.770 --> 00:15:16.940 align:start position:0% to explain without example that's okay he<00:15:11.280> will<00:15:11.430> see<00:15:12.590> so<00:15:13.590> what<00:15:13.770> else<00:15:13.920> do<00:15:14.010> we<00:15:14.040> have<00:15:15.950> yeah 00:15:16.940 --> 00:15:16.950 align:start position:0% he will see so what else do we have yeah 00:15:16.950 --> 00:15:23.180 align:start position:0% he will see so what else do we have yeah so<00:15:20.720> we<00:15:21.720> plan<00:15:21.930> to<00:15:22.080> add<00:15:22.230> algebraic<00:15:22.770> data<00:15:22.890> types 00:15:23.180 --> 00:15:23.190 align:start position:0% so we plan to add algebraic data types 00:15:23.190 --> 00:15:26.090 align:start position:0% so we plan to add algebraic data types and<00:15:23.520> as<00:15:23.850> I<00:15:23.880> said<00:15:24.030> templates<00:15:24.600> but<00:15:25.440> it's 00:15:26.090 --> 00:15:26.100 align:start position:0% and as I said templates but it's 00:15:26.100 --> 00:15:29.450 align:start position:0% and as I said templates but it's probably<00:15:27.260> too<00:15:28.260> hard<00:15:28.500> to<00:15:28.650> explain<00:15:28.950> the<00:15:29.220> source 00:15:29.450 --> 00:15:29.460 align:start position:0% probably too hard to explain the source 00:15:29.460 --> 00:15:31.430 align:start position:0% probably too hard to explain the source code<00:15:29.640> in<00:15:29.820> this<00:15:29.940> talk<00:15:30.240> and<00:15:30.960> there's<00:15:31.260> another 00:15:31.430 --> 00:15:31.440 align:start position:0% code in this talk and there's another 00:15:31.440 --> 00:15:34.310 align:start position:0% code in this talk and there's another slide<00:15:32.190> with<00:15:32.520> even<00:15:32.880> more<00:15:33.150> complicated<00:15:33.810> future 00:15:34.310 --> 00:15:34.320 align:start position:0% slide with even more complicated future 00:15:34.320 --> 00:15:35.900 align:start position:0% slide with even more complicated future solidity<00:15:34.680> code 00:15:35.900 --> 00:15:35.910 align:start position:0% solidity code 00:15:35.910 --> 00:15:38.450 align:start position:0% solidity code and<00:15:36.030> I<00:15:36.300> would<00:15:36.570> just<00:15:36.690> encourage<00:15:36.900> you<00:15:37.470> to<00:15:37.680> take<00:15:38.400> a 00:15:38.450 --> 00:15:38.460 align:start position:0% and I would just encourage you to take a 00:15:38.460 --> 00:15:41.150 align:start position:0% and I would just encourage you to take a look<00:15:38.670> at<00:15:38.820> the<00:15:39.030> slides<00:15:39.690> later<00:15:40.020> and<00:15:40.410> read<00:15:41.010> the 00:15:41.150 --> 00:15:41.160 align:start position:0% look at the slides later and read the 00:15:41.160 --> 00:15:44.810 align:start position:0% look at the slides later and read the comments<00:15:42.050> yeah<00:15:43.050> this<00:15:43.260> is<00:15:43.380> just<00:15:43.620> a<00:15:43.770> rough<00:15:44.670> idea 00:15:44.810 --> 00:15:44.820 align:start position:0% comments yeah this is just a rough idea 00:15:44.820 --> 00:15:48.500 align:start position:0% comments yeah this is just a rough idea of<00:15:45.030> how<00:15:45.390> it<00:15:45.660> could<00:15:45.930> look<00:15:45.960> like<00:15:46.110> so<00:15:46.530> i<00:15:47.300> hope<00:15:48.300> that 00:15:48.500 --> 00:15:48.510 align:start position:0% of how it could look like so i hope that 00:15:48.510 --> 00:15:50.870 align:start position:0% of how it could look like so i hope that the<00:15:48.720> urls<00:15:49.530> of<00:15:49.830> the<00:15:49.950> slides<00:15:50.190> are<00:15:50.430> published 00:15:50.870 --> 00:15:50.880 align:start position:0% the urls of the slides are published 00:15:50.880 --> 00:15:53.270 align:start position:0% the urls of the slides are published sooner<00:15:51.240> for<00:15:51.420> the<00:15:51.480> conference<00:15:51.900> and<00:15:52.140> yeah<00:15:53.100> i 00:15:53.270 --> 00:15:53.280 align:start position:0% sooner for the conference and yeah i 00:15:53.280 --> 00:15:55.460 align:start position:0% sooner for the conference and yeah i think<00:15:53.400> there<00:15:53.760> we<00:15:54.360> also<00:15:54.510> have<00:15:54.750> relevant<00:15:55.290> reddit 00:15:55.460 --> 00:15:55.470 align:start position:0% think there we also have relevant reddit 00:15:55.470 --> 00:15:59.270 align:start position:0% think there we also have relevant reddit post<00:15:55.500> them<00:15:56.540> okay<00:15:57.540> thank<00:15:58.260> you<00:15:58.320> thanks 00:15:59.270 --> 00:15:59.280 align:start position:0% post them okay thank you thanks 00:15:59.280 --> 00:16:06.120 align:start position:0% post them okay thank you thanks Christian 00:16:06.120 --> 00:16:06.130 align:start position:0% 00:16:06.130 --> 00:16:08.190 align:start position:0% you