Error code E0416

An identifier is bound more than once in a pattern.

Erroneous code example:

#![allow(unused)] fn main() { match (1, 2) { (x, x) => {} // error: identifier `x` is bound more than once in the // same pattern } }

Please verify you didn't misspell identifiers' name. Example:

#![allow(unused)] fn main() { match (1, 2) { (x, y) => {} // ok! } }

Or maybe did you mean to unify? Consider using a guard:

#![allow(unused)] fn main() { let (A, B, C) = (1, 2, 3); match (A, B, C) { (x, x2, see) if x == x2 => { /* A and B are equal, do one thing */ } (y, z, see) => { /* A and B not equal; do another thing */ } } }