php-grammarAn open source EBNF grammar for PHP.

Grammar explorer

PHP 8.5 Production

relational-expression

Read left to right. Select any rule to explore it.

relational-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: pipe-expressionpipe-expression"<""<="">"">="Explore production: pipe-expressionpipe-expression
Production LiteralBranch: choiceBypass: optionalLoop: repeat
EBNF source
relational-expression =
    pipe-expression , [ ( "<" | "<=" | ">" | ">=" ) , pipe-expression ] ;

Explore next

pipe-expression
Referenced by 2
equality-expressionequality-prefix-context

Take it with you

The grammar, in plain text.

For reading, building tools, and exploring PHP.
Free to use under the MIT license.

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.

Explore the project and contribute