Stage _ Draft / July 25, 2017

Private field and method shorthand

Introduction

This proposal introduces shorthand for accessing private fields and methods. See the explainer for motivation and status.

1Syntax

PrimaryExpression[Yield, Await]:this IdentifierReference[?Yield, ?Await] Literal ArrayLiteral[?Yield, ?Await] ObjectLiteral[?Yield, ?Await] FunctionExpression ClassExpression[?Yield, ?Await] GeneratorExpression AsyncFunctionExpression RegularExpressionLiteral TemplateLiteral[?Yield, ?Await] CoverParenthesizedExpressionAndArrowParameterList[?Yield, ?Await] PrivateName

2Semantics

2.1Static Semantics: Early Errors

UnaryExpression:deleteUnaryExpression

2.2Static Semantics: AllPrivateNamesValid

PrimaryExpression:PrivateName
  1. If StringValue of PrivateName is in names, return true.
  2. Return false.

2.3Runtime Semantics: Evaluation

PrimaryExpression:PrivateName
  1. Let baseValue be ? ResolveThisBinding().
  2. Let bv be ? RequireObjectCoercible(baseValue).
  3. Let fieldNameString be the PrivateStringValue of PrivateName.
  4. Return MakePrivateReference(bv, fieldNameString).

ACopyright & Software License

Copyright Notice

© 2017 Daniel Ehrenberg, Yehuda Katz

Software License

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