This is a deprecated document. The document with all updated changes for this proposal has been merged and available as an unified document here.
This document adds to the class fields proposal by introducing private methods and accessors. See the explainer for an overview.
This specification draft is phrased as a diff against the class fields proposal.
With parameter className.
constructor(... args){ super (...args);}
using the syntactic grammar with the constructor( ){ }
using the syntactic grammar with the "derived"
."constructor"
, F)."method"
or "accessor"
,"method"
.With parameters homeObject and enumerable.
"prototype"
),enumerable, and "prototype"
.
"static"
.
"get"
)."accessor"
."accessor"
."set"
)."accessor"
."accessor"
."prototype"
, PropertyDescriptor{[[Value]]: prototype, [[Writable]]: "prototype"
, PropertyDescriptor { [[Value]]: prototype, [[Writable]]: super
Keyword
The [[Construct]] internal method for an ECMAScript Function object F is
called with parameters argumentsList and newTarget. argumentsList is
a possibly empty
"base"
, then"%ObjectPrototype%"
)."base"
, then"base"
, return The Private Name specification type is used to describe a globally unique record which represents a private fieldclass element (field, method, or accessor). A Private Name may be installed on any ECMAScript object with the PrivateFieldAdd internal algorithm, and then read or written using
Each Private Name holds the following information:
Field | Type | For which types is it present | Description |
---|---|---|---|
[[Description]] |
|
All |
The string value passed to NewPrivateName when creating this |
[[Kind]] |
"field" , "method" or "accessor"
|
All | Indicates what the private name is used for. |
[[Brand]] | an ECMAScript value |
"method" or "accessor"
|
The "original" class of the private method or accessor; checked for in the [[PrivateBrands]] internal slot of instances before access is provided. |
[[Value]] | Function |
"method"
|
The value of the private method. |
[[Get]] | Function |
"accessor"
|
The getter for a private accessor. |
[[Set]] | Function |
"accessor"
|
The setter for a private accessor. |
In addition to [[PrivateFieldValues]], all ECMAScript objects have a new additional internal slot, [[PrivateBrands]], which is an initially empty
Although this specification uses logic of a [[PrivateBrand]]
"field"
,"method"
,"accessor"
."field"
,"method"
, throw a "accessor"
.© 2021 Daniel Ehrenberg, Jeff Morrison, Kevin Smith, Kevin Gibbons
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