php-grammarAn open source EBNF grammar for PHP.

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PHP 8.5 Production

encapsulated-variable

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encapsulated-variable 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: variablevariableExplore production: variablevariable"["Explore production: encapsulated-offsetencapsulated-offset"]"Explore production: variablevariableExplore production: object-operatorobject-operatorExplore production: identifieridentifierExplore production: variablevariableExplore production: nullsafe-object-operatornullsafe-object-operatorExplore production: identifieridentifier"${"Explore production: expressionexpression"}""${"Explore production: identifieridentifier"}""${"Explore production: identifieridentifier"["Explore production: expressionexpression"]""}""{"Explore production: variable-expressionvariable-expression"}"
Production LiteralBranch: choiceBypass: optionalLoop: repeat
EBNF source
encapsulated-variable =
      variable
    | variable , "[" , encapsulated-offset , "]"
    | variable , object-operator , identifier
    | variable , nullsafe-object-operator , identifier
    | "${" , expression , "}"
    | "${" , identifier , "}"
    | "${" , identifier , "[" , expression , "]" , "}"
    | "{" , variable-expression , "}" ;

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variable encapsulated-offset object-operator identifier nullsafe-object-operator expression variable-expression
Referenced by 1
encapsulated-string-part

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

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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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