On Tuesday, 10 February 2015 at 15:57:28 UTC, Zach the Mystic
wrote:
On Tuesday, 10 February 2015 at 15:49:24 UTC, Zach the Mystic
wrote:
As already pointed out in the other thread, there is a
non-breaking variant of (3):
3a. Keep named @trusted functions, allow @system blocks
inside them, but only treat those with @system blocks with
the new semantics.
But they *have* no semantics without disallowing @system code
in the rest of the @trusted function.
Wait a second... you're totally right. That is a cool
solution. The only hiccup is that it might be hard to
implement in the compiler because of flow tracking (i.e. the
error comes before the @system block, forcing a recheck of all
preceding functions.).
I'm sorry I misread you at first -- this is actually really
cool (notwithstanding the hiccup)!
No problem!
At first I thought it was only a nice deprecation path, but I
realised that the intermediate stage could even be kept
indefinitely.
It probably wouldn't be too complicated to implement, because
semantic analysis already happens in several stages. I think
@safe checks happen relatively late, which means that there has
already been one complete traversal of the functions AST which
can take a note whenever it sees an @system block. If not, it
would have to do a simple scan first, which doesn't seem to
complicated either.
