Parse PHP Doc Blocks

doc_block.php

<?php

class DocBlock {
    
    public $docblock,
           $description = null,
           $all_params = array();
    
    /**
     * Parses a docblock;
     */
    function __construct($docblock) {
        if( !is_string($docblock) ) {
            throw new Exception("DocBlock expects first parameter to be a string");
        }
        
        $this->docblock = $docblock;
        $this->parse_block();
    }
    
    /**
     * An alias to __call();
     * allows a better DSL
     *
     * @param string $param_name
     * @return mixed
     */
    public function __get($param_name) {
        return $this->$param_name();
    }
    
    /**
     * Checks if the param exists
     * 
     * @param string $param_name
     * @return mixed
     */
    public function __call($param_name, $values = null) {
        if( $param_name == "description" ) {
            return $this->description;
        }else if( isset($this->all_params[$param_name]) ) {
            $params = $this->all_params[$param_name];
            
            if( count($params) == 1 ) {
                return $params[0];
            }else {
                return $params;
            }
        }
        
        return null;
    }
    
    /**
     * Parse each line in the docblock
     * and store the params in `$this->all_params`
     * and the rest in `$this->description`
     */
    private function parse_block() {
        // split at each line
        foreach(preg_split("/(\r?\n)/", $this->docblock) as $line){
            
            // if starts with an asterisk
            if( preg_match('/^(?=\s+?\*[^\/])(.+)/', $line, $matches) ) {
                
                $info = $matches[1];
                
                // remove wrapping whitespace
                $info = trim($info);
                
                // remove leading asterisk
                $info = preg_replace('/^(\*\s+?)/', '', $info);
                
                // if it doesn't start with an "@" symbol
                // then add to the description
                if( $info[0] !== "@" ) {
                    $this->description .= "\n$info";
                    continue;
                }else {
                    // get the name of the param
                    preg_match('/@(\w+)/', $info, $matches);
                    $param_name = $matches[1];
                    
                    // remove the param from the string
                    $value = str_replace("@$param_name ", '', $info);
                    
                    // if the param hasn't been added yet, create a key for it
                    if( !isset($this->all_params[$param_name]) ) {
                        $this->all_params[$param_name] = array();
                    }
                    
                    // push the param value into place
                    $this->all_params[$param_name][] = $value;
                    
                    continue;
                }
            }
        }
    }
}

example.php

<?php

class Person {
    
    /**
     * This is the description of my
     * doc comment
     *
     * @param string $name
     * @param integer $age
     *
     * @author Baylor Rae'
     */
    public static function greet($name, $age) {
        echo "Hello $name, you are $age";
    }
}

$r = new ReflectionMethod('Person', 'greet');
$block = $r->getDocComment();

$doc_block = new DocBlock($block);

echo 'Author: ' . $doc_block->author;

echo 'Params:';
print_r($doc_block->params);