php-grammarAn open source EBNF grammar for PHP.

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PHP 8.5 Production

coalesce-prefix-context

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coalesce-prefix-context 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: boolean-or-prefix-contextboolean-or-prefix-contextExplore production: boolean-or-expressionboolean-or-expression"??"Explore production: boolean-or-expressionboolean-or-expression"??"Explore production: boolean-or-prefix-contextboolean-or-prefix-context
Production LiteralBranch: choiceBypass: optionalLoop: repeat
EBNF source
coalesce-prefix-context =
    boolean-or-prefix-context | boolean-or-expression , "??" , { boolean-or-expression , "??" } , [ boolean-or-prefix-context ] ;

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boolean-or-prefix-context boolean-or-expression
Referenced by 1
conditional-prefix-context

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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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