parseExpression in Twig - php

Question

I am integrating Twig in an existing project.
I am writing a token parser to parse a custom tag that is similiar to the {% render %} tag.
My tag looks like:
{% mytag 'somestring' with { 'name': name, 'color': 'green' } %}
where name is defined by {% set name = 'foo' %}
I am able to parse somestring without any issues.
This is the code used to parse the stuff in the with{ }:
$Stream = $this->parser->getStream();
if ( $Stream->test( \Twig_Token::NAME_TYPE, 'with' ) )
{
$Stream->next();
$parsedParameters = $this->parser->getExpressionParser()->parseExpression();
$parameters = $this->parser->getEnvironment()->compile( $parsedParameters );
var_dump( $parameters ); //string 'array( "name" => $this->getContext( $context, "name" ), "color" => "green" )' (length=72)
foreach ( $parsedParameters->getIterator() as $parameter )
{
//var_dump($ parameter->getAttribute('value') );
}
}
My goal is to turn 'name': name, 'color': 'green' into an associative array within the token parser:
array(
'name' => 'foo',
'color': 'green',
)
As the documentation is quite sparse and the code in the library is uncommented, I am not sure how to do this. If I loop through $parsedParameters, I get 4 elements consisting of the array key and an array value. However, as name is a variable with a type Twig_Node_Expression_Name, I am unsure as to how I can compile it to get the compiled value. Currently, I have found a way to compile that node, but all it gives me is a string containing a PHP expression which I can't use.
How can I turn the parsed expression into an associative array?

Answer 1

Okey. I guess I was able to solve that. Not to pretty, but should work.
$Stream = $this->parser->getStream();
if ( $Stream->test( \Twig_Token::NAME_TYPE, 'with' ) )
{
$Stream->next();
$parsedParameters = $this->parser->getExpressionParser()->parseExpression();
$parameters = $this->parser->getEnvironment()->compile( $parsedParameters );
var_dump( $parameters ); //string 'array( "name" => $this->getContext( $context, "name" ), "color" => "green" )' (length=72)
$index = null;
$value = null;
foreach ( $parsedParameters->getIterator() as $parameter )
{
if ( $parameter->hasAttribute( 'value' ) )
{
$index = $parameter->getAttribute( 'value' );
}
elseif ( $parameter->hasAttribute( 'name' ) )
{
$value = $parameter->getAttribute( 'name' );
}
if ( isset( $index, $value ) )
{
$params[ $index ] = $value;
$index = null;
$value = null;
}
}
}
So here I have array params, that I can pass to Custom node.
$params = var_export( $properties['params'], true );
unset( $fieldProperties['params'] );
Now I just did following:
$Compiler
->write( "\$params = array();\n" )
->write( "foreach ( {$params} as \$searchFor => \$replaceWith )\n" )
->write( "{\n" )
->write( "\t\$params[ \$searchFor ] = str_replace( \$replaceWith, \$context[\$replaceWith], \$replaceWith );\n" )
->write( "}\n" )
->write( "var_dump( \$params );\n" );
This should be it.
Also I see, that you where talking about TokenParser, but sadly I haven't found the solution to turn it over there.