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Rust errors / Names, paths and imports

Rust compiler error · checked with rustc 1.99.0

Rust error E0124: field `field1` is already declared

What it meansA struct was declared with two fields having the same name.

What rustc prints

error[E0124]: field `field1` is already declared
 --> main.rs:3:5
  |
2 |     field1: i32,
  |     ----------- `field1` first declared here
3 |     field1: i32, // error: field is already declared
  |     ^^^^^^^^^^^ field already declared

Real output of rustc 1.99.0 compiling the official example below (2021 edition). Your names and line numbers will differ; the first line is the part to match.

E0124Names, paths and imports
Activein rustc 1.99.0
8related errors linked below

The compiler team's explanation

A struct was declared with two fields having the same name.

Erroneous code example:

struct Foo {
    field1: i32,
    field1: i32, // error: field is already declared
}

Please verify that the field names have been correctly spelled. Example:

struct Foo {
    field1: i32,
    field2: i32, // ok!
}

From rustc --explain E0124 (1.99.0), part of the Rust project, MIT or Apache-2.0. Official page.

Related errors

All 518 Rust error codes · Rust crate data · Glossary

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