@putout/plugin-extract-sequence-expressions

The comma operator (,) evaluates each of its operands (from left to right) and returns the value of the last operand. This lets you create a compound expression in which multiple expressions are evaluated, with the compound expression's final value being the value of the rightmost of its member expressions.

(c) MDN

????Putout plugin adds ability to extract sequence expressions. Check out in ????Putout Editor.

☝️Remember, when you writing a transform you can skip all parts related to extracting sequence expressions and just reuse current plugin it will make your code simpler and less error prone.

Install

npm i @putout/plugin-extract-sequence-expressions -D

Rule

{
    "rules": {
        "extract-sequence-expressions": "on"
    }
}

❌ Example of incorrect code

(module.exports.x = 1, module.exports.y = 2);

fn((a, b));
(fn(a), 'hello');

(fn(a), b = 3);
(fn(a), fn(b));

if ((a, b, c)) {}

✅ Example of correct code

module.exports.x = 1;
module.exports.y = 2;

fn(a, b);
fn(a, 'hello');

fn(a);
b = 3;

fn(a);
fn(b);

a;
b;

if (c) {}

Comparison

Linter	Rule	Fix
???? Putout	`extract-sequence-expressions`	✅
⏣ ESLint	`no-sequences`	❌

@putout/plugin-extract-sequence-expressions

Install

Rule

❌ Example of incorrect code

✅ Example of correct code

Comparison

License

Current Tags

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