PHP Expression language

dev-master / 0.1.x-dev 2013-09-02 08:28 UTC

This package is not auto-updated.

Last update: 2021-09-11 02:42:39 UTC


The purpose of this library is to provide a common base for an PHP Expression Language.

This is not really a creative library since it burrows almost all the code from the great JMSSecurityExtraBundle which already defines more or less such a base for a powerful EL (Expression Language).

The idea is to take this code outside of the Johannes's bundle and to standardize it.

Simple usage

$compiler = new ExpressionCompiler();
$evaluator = eval($compiler->compileExpression(new Expression("date.format(format)")));

$context = array(
    'date' => new \DateTime(),
    'format' => 'Y',
$result = $evaluator($context);

echo $result; // 2013

Adding a custom function compiler

The isNumber() function expression:

  1. First you need to create a compiler for your function

    namespace My\Expression\Compiler\Func;
    use Pel\Expression\Compiler\Func\FunctionCompilerInterface;
    use Pel\Expression\ExpressionCompiler;
    use Pel\Expression\Ast\FunctionExpression;
    use Pel\Exception\RuntimeException;
    class IsNumberFunctionCompiler implements FunctionCompilerInterface
        public function getName()
            return 'isNumber';
        public function compilePreconditions(ExpressionCompiler $compiler, FunctionExpression $function)
            if (1 !== count($function->args)) {
                throw new RuntimeException(sprintf('The isNumber() function expects exactly one argument, but got "%s".', var_export($function->args, true)));
        public function compile(ExpressionCompiler $compiler, FunctionExpression $function)
  2. Next, after having instanciated the ExpressionCompiler, you just need to register your custom function compiler

    $compiler = new ExpressionCompiler();
    $compiler->addFunctionCompiler(new IsNumberFunctionCompiler());
    $evaluator = eval($compiler->compileExpression(new Expression("isNumber('1234')")));
    var_dump(call_user_func($evaluator, array()));
    // bool(true)
    $evaluator = eval($compiler->compileExpression(new Expression("isNumber('1234abc')")));
    var_dump(call_user_func($evaluator, array()));
    // bool(false)


This bundle is under the MIT license. See the complete license in library: