README

A set of Bison skeleton files that can be used to generate a Bison parser written in PHP.

Requirements:

• PHP >= 7.4
• Bison >= 3.8

Installation

composer require --dev mrsuh/php-bison-skeleton

Usage

bison -S vendor/mrsuh/php-bison-skeleton/src/php-skel.m4 -o parser.php grammar.y

Posts

• PHP Skeleton for Bison
• AST parser with PHP and Bison
• Nginx parser with PHP and Bison
• JSON parser with PHP and Bison

Docker

• Bison docker image

Example

grammar.y

%define api.parser.class {Parser} %token T_NUMBER %left '-' '+'  %% start:  expression { printf("%d\n", $1); } ;  expression:  T_NUMBER { $$ = $1; } | expression '+' expression { $$ = $1 + $3; } | expression '-' expression { $$ = $1 - $3; } ;  %% class Lexer implements LexerInterface {  private array $words;  private int $index = 0;  private int $value = 0;   public function __construct($resource)  {  $this->words = explode(' ', trim(fgets($resource))); } public function yyerror(string $message): void { printf("%s\n", $message); } public function getLVal() { return $this->value; } public function yylex(): int { if ($this->index >= count($this->words)) { return LexerInterface::YYEOF; } $word = $this->words[$this->index++]; if (is_numeric($word)) { $this->value = (int)$word; return LexerInterface::T_NUMBER; } return ord($word); } } $lexer = new Lexer(STDIN); $parser = new Parser($lexer); if (!$parser->parse()) { exit(1); }

bison -S vendor/mrsuh/php-bison-skeleton/src/php-skel.m4 -o parser.php grammar.y

php parser.php <<< "1 + 2" 3

See more examples in the folder

Tests

composer test