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Understanding and Resolving Rust Error E0026

Error E0026: Nonexistent Struct Field Extraction

In the Rust programming language, error E0026 occurs when a struct pattern tries to extract a field that doesn't exist. This error typically happens when using field pattern shorthands and referring to the struct field by a different name.

Erroneous Code Example

struct Thing {
    x: u32,
    y: u32,
}

let thing = Thing { x: 0, y: 0 };

match thing {
    Thing { x, z } => {} // error: `Thing::z` field doesn't exist
}

In the example above, the code tries to match the 'thing' struct with 'Thing { x, z }'. However, the field 'z' doesn't exist in the 'Thing' struct, causing the E0026 error.

Resolving Error E0026

To resolve this error, you should rename the improperly named struct field. Struct fields should be identified by the name used before the colon, so struct patterns should resemble the declaration of the struct type being matched. Use an explicit rename with the correct field, and the error will be resolved.

Corrected Code Example

struct Thing {
    x: u32,
    y: u32,
}

let thing = Thing { x: 0, y: 0 };

match thing {
    Thing { x, y: z } => {} // we renamed `y` to `z`
}

In this corrected example, we renamed the 'y' field to 'z' explicitly, following the correct struct pattern syntax and resolving the E0026 error.

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