Explain $! and $/ in start block #2804
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doc/Language/control.pod6
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| say $promise.result; # OUTPUT: «42» | ||
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| Note that code executed this way does not have access to special variables L«C<$!>|/syntax/$!» | ||
| and L«C<$/>|/syntax/$/» of its outer block, but receives new ones. |
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Not sure if it's worth mentioning the motivation for this: so that regex matches and try expressions executed in the asynchronous task will have their per-task state.
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Hmmm, we probably should. Also, can you please explain thunks part? I know the term in its general meaning, we even have a glossary item, but in fact it tells no useful info, and the changelog entry says "start blocks and thunks get fresh
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When we have start { blah } it's obvious that there's a new scope there: the start has a block. But when we have start blah there's no visible block there, but in fact we are creating an object of type Code that contains the blah. That Code object - which doesn't map to any visible block in the code - is the thunk.
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Ah, and the reason we must do this is because we don't want blah to execute now, but over on the thread pool - which is the point of start! :)
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This is not resolved yet, right? Can you please take a look and solve it?
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It is not, thanks for reminding.
I will address it a bit later today.
Addresses
start blocks and thunks get fresh $/ and $!from 6.d changelog.On the other hand, I am not sure where we can indicate
thunkspart. Any ideas?