There were several items on the agenda, this post focuses on feature proposals and their progress from the 104th TC39 meeting [8th-10th October 2024].

Stage 1:

• Representing Measures: Proposal to format and represent measurements with proper units in JavaScript.

• Immutable ArrayBuffers: Adds immutable variants of ArrayBuffer to ensure buffer contents cannot be changed.

• Array.zip: A method that creates an array of arrays, where each sub-array contains elements at the same index from multiple input arrays.

Stage 2:

• Iterator chunking: Adds a utility to create chunks from iterators, returning fixed-size groups of elements.

• Extractors: Provides utilities for data extraction, allowing structured data to be parsed and manipulated.

• Structs: Introduces structured data types that are more predictable and memory-efficient for JavaScript.

Stage 2.7:

• Error.isError: Enhances the Error.isError method for better error detection.

• Iterator Sequencing: Adds sequencing utilities to iterators, allowing more control over execution order.

Stage 3:

• Atomics.pause: Introduces a mechanism to pause execution at atomic operations for concurrency management.

Stage 4:

• Promise.try: Provides a utility to handle synchronous exceptions within promises more easily.

• Sync Iterator Helpers: Extends iterators with helper methods to improve their usability in synchronous contexts.

• Import Attributes: Proposal for syntax to import ES modules with assertions

• JSON modules: Proposal to import JSON files as modules.

• RegExp Modifiers: Enhances regular expressions with additional modifiers, allowing more flexible pattern matching.

Additionally The TG4 source maps spec got conditional consensus.