php-grammarAn open source EBNF grammar for PHP.

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PHP 8.5 Production

heredoc-string

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heredoc-string 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."b""B""<<<"" ""\t"Explore production: heredoc-labelheredoc-label"""Explore production: heredoc-labelheredoc-label"""Explore production: newlinenewlineExplore production: heredoc-bodyheredoc-body" ""\t"Explore production: heredoc-labelheredoc-label
Production LiteralBranch: choiceBypass: optionalLoop: repeat
EBNF source
heredoc-string =
    [ "b" | "B" ] , "<<<" , { " " | "\t" } ,
    ( heredoc-label | "\"" , heredoc-label , "\"" ) , newline ,
    heredoc-body , { " " | "\t" } , heredoc-label ;

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heredoc-label newline heredoc-body
Referenced by 1
string-literal

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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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