Function argument names should be unique

Docs > Code Analysis > Static Analysis Rules > Function argument names should be unique

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Metadata

ID: typescript-common-security/unique-function-arguments

Language: TypeScript

Severity: Warning

Category: Error Prone

Description

A function’s parameter names should all be unique. Otherwise, a latter parameter will overwrite the former parameter. This behavior can lead to unintended bugs and it difficult to debug in the future.

Non-Compliant Code Examples

function addition(foo: number, bar: number, foo: number) {
  console.log(foo + bar + foo);
}

addition(1, 2, 3); // outputs 8

Compliant Code Examples

function addition(foo: number, bar: number, baz: number) {
  console.log(foo + bar + baz);
}

export function useEditorStateTransform<Input, Output>(
    input: Input,
    transformByState: StateFunctions<Input, Output>,
    defaultValue: Input | null = input,
): Input | Output | null {
}

addition(1, 2, 3); // outputs 6