/tg4

TC39-TG4: Source map specification

ECMAScript - Source Maps Task Group (TC39-TG4)

This repository contains documents, agendas, and notes for the ECMAScript - Source maps Task Group (TC39-TG4).

See Scope for our mandate.

Specification

Meetings

Meetings are bi-weekly. The meetings appear on the TC39 private calendar.

Folks

Scope

To improve and evolve the existing informal source map specification into an Ecma standard. This specification defines a JSON-based format describing a mapping of compiled/optimized code (including CSS and ECMAScript® code) into its original source, including metadata such as the mapping of certain names. The goal is to improve the development/debugging experience of source map usage, including for ECMAScript®.

Programme of work

  1. To complete and correct the existing source map specification, including:
    • To define the source map specification strongly enough that it can be determined whether both producers and consumers are “conformant”, leading to well-defined fixes.
    • To produce a conformance test suite against this stronger definition.
    • To evolve the existing source map specification rather than creating a new system (e.g., based on DWARF).
  2. On that basis, to improve source map expressiveness in various ways, including:
    • To create additional source map capabilities for improving the mapping of names, including function, variable, and property mappings.
    • To improve the association of a source map to the code it refers to, with various possible mechanisms.