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mnemnion/constr.rs

Created December 3, 2014 17:42
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Constants aren't literal?
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constr.rs
use std::fmt;
const FORMATTER: &'static str = "{}" ;
fn main() {
let x = 5i;
println! (FORMATTER, x);
}
@mnemnion
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mnemnion commented Dec 3, 2014

This produces the error /src/main.rs:11:15: 11:24 error: format argument must be a string literal. /src/main.rs:11 println! (FORMATTER, x);

How is this anything but a string literal? I plan to put FORMATTER in a base file and reuse it several times, seeking the usual advantages: semantics, and a single place from which to change or configure the constant.

@kmcallister
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Macro expansion happens before name resolution, so I think this would be pretty hard to fix :/

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