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      • Array.prototype.{flat,flatMap} S4

      Proposal details
      Proposal overview

      This proposal aims to add two array methods to ECMAScript: flat(), which flattens nested arrays, and flatMap(), which maps elements and flattens the result by one level.

      Note

      The README below comes from the upstream repository and may contain outdated stage or status metadata. Use the proposal details above as the current source of truth.

      Array.prototype.{flat,flatMap}

      A proposal to add Array.prototype.flat (formerly known as Array.prototype.flatten) and Array.prototype.flatMap to ECMAScript.

      Status

      This proposal is at stage 4 of the TC39 Process.