rustc: Add long diagnostics for E0165

This commit is contained in:
Ruud van Asseldonk 2015-04-14 20:11:04 +02:00
parent c45eacdbc6
commit 33dca5e3ad
1 changed files with 20 additions and 1 deletions

View File

@ -131,6 +131,26 @@ let Irrefutable(x) = irr;
foo(x);
"##,
E0165: r##"
A while-let pattern attempts to match the pattern, and enters the body if the
match was succesful. If the match is irrefutable (when it cannot fail to match),
use a regular `let`-binding inside a `loop` instead. For instance:
struct Irrefutable(i32);
let irr = Irrefutable(0);
// This fails to compile because the match is irrefutable.
while let Irrefutable(x) = irr {
...
}
// Try this instead:
loop {
let Irrefutable(x) = irr;
...
}
"##,
E0297: r##"
Patterns used to bind names must be irrefutable. That is, they must guarantee
that a name will be extracted in all cases. Instead of pattern matching the
@ -239,7 +259,6 @@ register_diagnostics! {
E0152,
E0158,
E0161,
E0165,
E0170,
E0261, // use of undeclared lifetime name
E0262, // illegal lifetime parameter name