php-grammarAn open source EBNF grammar for PHP.

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PHP 8.5 Production

yield-key-expression

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yield-key-expression railroad diagramRead left to right. Branches are alternatives, bypasses are optional, and loops repeat. Select a production to explore it. The EBNF and linked references follow below.Explore production: yield-from-expressionyield-from-expressionExplore production: yield-from-prefix-contextyield-from-prefix-context"yield"Explore production: yield-keyyield-key"=>"Explore production: yield-key-expressionyield-key-expression
Production LiteralBranch: choiceBypass: optionalLoop: repeat
EBNF source
yield-key-expression =
    yield-from-expression
    | [ yield-from-prefix-context ] , "yield" , yield-key , "=>" , yield-key-expression ;

Explore next

yield-from-expression yield-from-prefix-context yield-key yield-key-expression
Referenced by 3
yield-expressionyield-key-expressionclosed-yield-yield-expression

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php.ebnfPHP 8.5 · Canonical EBNF grammar php.mdPHP 8.5 · Grammar & source contract

A shared understanding of PHP.

php-grammar is an open source project documenting PHP syntax in a consistent, tool-independent format. The EBNF describes syntax; the accompanying specification defines lexical rules and contextual constraints.

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