File modules/dsl/ast/DslAssignment.class.php

Last commit: Fri Jul 1 18:09:05 2022 +0200	Jan Dankert	New: Bugfixes and much more string and array functions for the DSL.


     1 <?php
     2 
     3 namespace dsl\ast;
     4 
     5 use dsl\DslParserException;
     6 use dsl\DslRuntimeException;
     7 use dsl\DslToken;
     8 
     9 class DslAssignment implements DslStatement
    10 {
    11 	private $target = [];
    12 	private $value;
    13 
    14 	/**
    15 	 * DslAssignment constructor.
    16 	 * @param $target DslStatement
    17 	 * @param $value DslStatement
    18 	 * @throws DslParserException
    19 	 */
    20 	public function __construct( $target, $value )
    21 	{
    22 		//echo "<h5>Assignment:</h5><pre>"; var_export( $target ); var_export($value); echo "</pre>";
    23 
    24 		$this->target = $target;
    25 		$this->value  = $value;
    26 	}
    27 
    28 	/**
    29 	 * @param array $context
    30 	 * @return mixed|void
    31 	 * @throws DslRuntimeException
    32 	 */
    33 	public function execute( & $context ) {
    34 
    35 		$value = $this->value->execute( $context );
    36 
    37 		// if the variable is not already bound in this context it will be created.
    38 		// there is no need for a "var" or "let". they are completely obsolete.
    39 		//if   ( ! array_key_exists( $this->target->name,$context ) )
    40 		//	throw new DslRuntimeException('variable \''.$this->target->name.'\' does not exist');
    41 
    42 		$context[ $this->target->name ] = $value;
    43 
    44 		return $value;
    45 	}
    46 
    47 	public function parse($tokens)
    48 	{
    49 		$this->target = new DslExpression();
    50 		$this->value  = new DslExpression();
    51 
    52 		$assignmentOperatorFound = false;
    53 		$targetToken = [];
    54 		$valueToken  = [];
    55 
    56 		foreach( $tokens as $token ) {
    57 
    58 			if   ( $token->type == DslToken::T_OPERATOR && in_array($token->value,['=','+='.'-=']) ) {
    59 				$assignmentOperatorFound = true;
    60 				continue;
    61 			}
    62 
    63 			if   ( ! $assignmentOperatorFound )
    64 				$targetToken[] = $token;
    65 			else
    66 				$valueToken[] = $token;
    67 		}
    68 
    69 		if  ( $assignmentOperatorFound ) {
    70 			$this->target->parse( $targetToken );
    71 			$this->value ->parse( $valueToken );
    72 		} else 	{
    73 			$this->value->parse( $targetToken );
    74 			$this->target = null;
    75 		}
    76 	}
    77 }



Download modules/dsl/ast/DslAssignment.class.php


History
Fri, 1 Jul 2022 18:09:05 +0200	Jan Dankert	New: Bugfixes and much more string and array functions for the DSL.
Mon, 6 Jun 2022 13:35:56 +0200	Jan Dankert	Change: Completely ignoring let,var,const statements.
Wed, 1 Jun 2022 00:11:40 +0200	Jan Dankert	New: DSL as a filter for number values
Sun, 29 May 2022 16:56:40 +0200	Jan Dankert	New: DSL with support for functions with return values, full arithmetic, object properties
Sat, 28 May 2022 18:00:13 +0200	Jan Dankert	New: DSL with a much better syntax parsing and support for assignments, conditions, ...
Wed, 25 May 2022 22:47:17 +0200	Jan Dankert	New: DSL (domain specific language) for code elements. The old way with PHP code ist not sandboxed and unsecure. This approach is a minimalistic, javascript-like, scripting engine. For now only simple function calls are possible, for example: alert("example");