From 2e90bd94de32c739733966bfac96cf35e9a08655 Mon Sep 17 00:00:00 2001 From: Tim Chevalier Date: Wed, 6 Apr 2011 17:56:44 -0700 Subject: Continued sketching out code for checking states against preconditions. It's still sketchy. I added a typestate annotation field to statements tagged stmt_decl or stmt_expr, because a stmt_decl statement has a typestate that's different from that of its child node. This necessitated trivial changes to a bunch of other files all over to the compiler. I also added a few small standard library functions, some of which I didn't actually end up using but which I thought might be useful anyway. --- src/lib/option.rs | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'src/lib/option.rs') diff --git a/src/lib/option.rs b/src/lib/option.rs index 29a6f6eb96b..66a41bcac68 100644 --- a/src/lib/option.rs +++ b/src/lib/option.rs @@ -38,6 +38,13 @@ fn is_none[T](&t[T] opt) -> bool { } } +fn from_maybe[T](&T def, &t[T] opt) -> T { + alt(opt) { + case (none[T]) { ret def; } + case (some[T](?t)) { ret t; } + } +} + // Local Variables: // mode: rust; // fill-column: 78; -- cgit 1.4.1-3-g733a5