About this Directory

This ‘strawman’ namespace is intended to contain proposals for the “ES-Harmony” language that are not yet approved harmony proposals, and to clearly separate them from the legacy ES4 pages.

• Concurrency, Asynchrony, and Distributed Programming
  • concurrency (markm)
  • deferred functions allow writing asynchronous code in a linear style where you would otherwise use callbacks and manual CPS (peterhal)
  • async functions. Like deferred functions but expressed as a library in terms of concurrency and generators.
• Exemplars, Inheritance
  • magic proto property (markm)
  • fixing override mistake (markm)
• Array
  • array create (crock)
    • also see Set Literal Prototype Operator
  • array subtypes, for allowing construction of array instances with prototype other than Array.prototype (olliej)
  • array statics (dherman)
  • Array.prototype.pushAll (dherman)
  • Array extras (dherman)
  • Array.prototype.has (arv)
• Number and Math Enhancements
  • more Math fun, see Alistair Braidwood's message
  • Spreadsheet comparing ECMAScript Math functions to various C/C++ math libraries
  • number compare (crock)
  • random-er, or a better (cryptographically strong) random number generator (see Mozilla bug 322529 and crypto.getRandomValues spec from Adam Barth)
  • simd number (johnmccutchan)
• String
  • string format (crock)
  • string format (shanjian)
• Syntax
  • block vs object literal
  • object extension literals (AllenWB). It now includes concepts from dherman’s batch assignment operator
• Functions
  • name property of functions (brendan)
  • parameters property of functions (crock)
  • function to string – greater specification for problematic Function.prototype.toString (markm, allen)
  • const functions (markm) now with a joining optimization
  • block lambda revival, an alternative to arrow function syntax with new semantics, after Smalltalk and Ruby (brendan)
  • fix function name binding (Allen) Make the binding of function names consistent between FunctionExpressions and FunctionDeclarations
  • soft bind (alex, arv, markm) A binding operator intermediate between JavaScript’s current loose binding and the tight binding of Function.prototype.bind.
  • bind operator, a concrete syntax for binding this and Function.prototype.call (dherman)
• Regular Expressions
  • regexp x flag (crock)
  • multiline regexps (brendan, crock)
  • Steve Levithan RegExp API improvements
• Modules
  • simple module functions (markm)
  • system, a place to put powerful objects provided by the embedding without having to introduce names into the global scope every time.
• Operators
  • default operator (crock, brendan)
  • existential operator (brendan)
  • modulo operator (crock)
  • has operator (crock)
  • batch assignment operator (dherman). See also object extension literals
  • define properties operator (allen)
• Value types
  • value types, requirements for first-class number-like objects with operators and (we hope) literal syntax (brendan)
  • operator overloading with double dispatch A straightforward way to specify and implement open-ended operator overloading (allenwb)
  • also see value objects (dherman)
  • value proxies, extending proxies to implement value types (cormac)
• Garbage collection
  • gc semantics Thoughts on specifying the semantics of garbage collection. (markm)
  • weak references and post-mortem finalization. (markm) see also: weak refs (dherman)
  • inherited explicit soft fields (markm) – an encapsulation-respecting alternative to private names above. See comparison at names vs soft fields.
• Data structures
  • typed arrays, similar to the above byte arrays, as originally defined by webgl (arun)
  • encapsulated hashcodes (allen – see also weak maps)
  • records (brendan, dherman)
  • tuples (brendan, dherman)
  • dicts (dherman)
  • weak refs (dherman) see also: weak references and post-mortem finalization. (markm)
• Loops, iteration, enumeration
  • iterator conveniences, an API for convenient construction of iterators (dherman)
  • enumeration, more fully-specified semantics for property enumeration in for-in loops (brendan, dherman)
  • simultaneous iteration, an extension to the for-of syntax for looping over multiple iterators simultaneously (dherman)
• Private Names providing unique, unforgeable property names
  • syntactic support for private names
  • interaction between proxies and private names
    • Follow-up strawman to propose a decoupling between proxies and private symbols
    • Another follow-up strawman: relationships.
• Proxies
  • revokable proxies to enable GC-friendly caretaker proxies.
• Similar declarative object extension mechanisms
  • scoped object extensions (peterhal)
• High Integrity Factories
  • traits semantics (tom)
  • guards A syntax for dynamic type-like checks (markm, waldemar)
  • trademarks Simple semantics for dynamic type-like checks (markm, waldemar)
• Versions and Configuration
  • versioning, the full versioning of script tag content and whole-frame/window object model monty (brendan)
• ast, a parser built into conforming Harmony implementations which returns a standard abstract syntax tree (dherman)
• extended Object API, standardizing some “missing” ES5 methods on Object. (tomvc)
  • object model reformation: Decoupling . and [ ] to enable used defined collections
• paren free, relaxing the rules about mandatory parentheses (brendan, dherman)
• completion let, a variation on let expressions that uses completions (dherman)
• debugger expressions, to extend the syntax of debugger to be an expression (dherman)
• Conditionals
  • catch guards, for conditionally catching exceptions (dherman)
  • pattern matching, a conditional form based on destructuring (dherman)
  • cond expressions, for concise linear nesting of conditional expressions (dherman)
• observe, better databinding via object change notifications
  • attach, support databinding via proxies
• Specification Techniques
  • Terminology, Revised specification terminology for some ECMAScript concepts, eliminate “host” and “native” object terminology.
• Internationalization support
  • Unicode support, tools to aid in using Unicode.
  • Identifier identification

• ECMASript object model and internal metaobject protocol (Allen)
  • subclassable-builtins How to make built-in constructors such as Array and Date “subclassable”.
  • ES5 internal methods and aligning them with Proxy handlers
  • ES5 internal nominal typing and generalizing usage of [[Class]]
  • Class method syntax
• minimal classes (dherman)
• maximally minimal classes
• do expressions (dherman)
• assert (dherman)
• value objects (dherman)
• data parallelism (dherman, brendan, rhudson, sherhut)
• Error stack (arv)

See the accepted proposals page.

See the deferred proposals page.

See the withdrawn proposals page.