default-param-last.md

Pattern: Default parameter before required parameters

Issue: -

Description

When default parameters appear before required parameters in a function signature, it becomes impossible to omit the optional arguments when calling the function. This forces developers to explicitly pass undefined for optional parameters.

Examples

Example of incorrect code:

function createUser(isAdmin = false, id) {}
createUser(undefined, "tabby");

Example of correct code:

function createUser(id, isAdmin = false) {}
createUser("tabby");