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@studnicky/v8/inline-arrow-functions ​

A dispatch map (an object literal whose values are handler functions) built once at module scope, or as a static class field, allocates its arrow-function values exactly once. The same map literal built inside a function body or an instance field re-allocates every arrow function on every invocation, which is pure churn for the garbage collector and defeats V8's ability to reuse a single closure. This rule flags multi-statement (block-body) arrow functions used as object-literal property values only when the enclosing literal is rebuilt per call — a module-scope const or static field is exempt, as are single-expression arrow bodies and property keys named callback, execute, handler, process, transform, transformAsync, or validate.

Fixable: No · Options: No · Suggested severity: error

✗ Incorrect ​

ts
function build() {
  return {
    a: (x) => { let y = x; return y; }
  };
}

✓ Correct ​

ts
const map = {
  a: (x) => { let y = x; return y; }
};