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      • Standardized Debug S1

      Proposal details
      Proposal overview

      This proposal standardizes debugging facilities across ECMAScript implementations by introducing two meta-property functions, debugger.log and debugger.break, which are identity functions and only valid in call expression form.

      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      The README below comes from the upstream repository and may contain outdated stage or status metadata.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.

      Standardized Debug

      This proposal is at Stage 1 of the TC39 Process.

      Motivation

      Different environments expose different APIs for interacting with debugger facilities. Some of them do not expose any APIs for this at all. This proposal aims to provide standardized debugging facilities across all ECMAScript implementations. Additionally, the APIs are constrained to be identity functions - that is, they return the value which is passed to them.

      This proposal suggests adding the following meta-property-functions to ES:

      • debugger.log ( v )
      • debugger.break ( [ v ] )

      Note that, like import(), they are only valid in call expression form. For example, x().then(debugger.break) would be invalid. You would have to do x().then((v) => debugger.break(v)). This limitation is in place to ensure these methods (particularly break) are only ever invoked from ECMAScript code.