Macro matches2::assert_matches

macro_rules! assert_matches {
    ($expression:expr, $(|)* $pattern:pat $(|$pattern_extra:pat)* $(if $ifguard:expr)*) => { ... };
    ($expression:expr, $(|)* $pattern:pat $(|$pattern_extra:pat)* $(if $ifguard:expr)*, $($msg:tt)+) => { ... };
}

Assert that an expression matches a refutable pattern.

Syntax: assert_matches!( expression , pattern [, error message ])

If the pattern does not match, this macro panics with the given error message or a default one that contains the pattern in it. NB: The error message is passed through to panic! verbatim, so you can do assert_matches!(..., "{}", 2).

Examples

#[macro_use]
extern crate matches2;

fn main() {
    let data = [1, 2, 3];
    assert_matches!(data.get(1), Some(_));
}