Yield

src/main/jay/grammars/php.jay

@@ -75,14 +75,17 @@ use xp\compiler\ast\DynamicInstanceCreationNode;
 use xp\compiler\ast\DynamicInstanceOfNode;
 use xp\compiler\ast\DynamicVariableReferenceNode;
 use xp\compiler\ast\NoopNode;
+use xp\compiler\ast\YieldNode;
 %}
 
 %left ','
 %left '(' ')'
+%right T_YIELD
 %left T_BOOLEAN_OR
 %left T_BOOLEAN_AND
 %right '=' T_ADD_EQUAL T_SUB_EQUAL T_MUL_EQUAL T_DIV_EQUAL T_CONCAT_EQUAL T_MOD_EQUAL T_SHR T_SHL T_AND_EQUAL T_OR_EQUAL T_XOR_EQUAL
 %left '?' ':'
+%nonassoc T_DOUBLE_ARROW
 %left '|'
 %left '^'
 %left '&'
@@ -143,6 +146,7 @@ use xp\compiler\ast\NoopNode;
 %token T_IN 364
 %token T_BREAK 365
 %token T_CONTINUE 366
+%token T_YIELD 367
 
 %token T_IF 370
 %token T_ELSE 371
@@ -591,6 +595,15 @@ expression:
   | T_CLONE expression { 
       $$= $yyLex->create(new CloneNode($2)); break;
     }
+  | T_YIELD {
+      $$= $yyLex->create(new YieldNode());
+    }
+  | T_YIELD expression {
+      $$= $yyLex->create(new YieldNode($2));
+    }
+  | T_YIELD expression T_DOUBLE_ARROW expression {
+      $$= $yyLex->create(new YieldNode($4, $2));
+    }
   | assignment { 
       $$= $yyLex->create(new AssignmentNode($1)); 
     }

src/main/jay/grammars/xp.jay

@@ -70,14 +70,17 @@ use xp\compiler\ast\LambdaNode;
 use xp\compiler\ast\WithNode;
 use xp\compiler\ast\ArmNode;
 use xp\compiler\ast\BracedExpressionNode;
+use xp\compiler\ast\YieldNode;
 %}
 
 %left ','
 %nonassoc T_ARROW
+%right T_YIELD
 %left T_BOOLEAN_OR
 %left T_BOOLEAN_AND
 %right '=' T_ADD_EQUAL T_SUB_EQUAL T_MUL_EQUAL T_DIV_EQUAL T_CONCAT_EQUAL T_MOD_EQUAL T_AND_EQUAL T_OR_EQUAL T_XOR_EQUAL
-%left '?' ':'
+%left '?'
+%nonassoc ':'
 %left '|'
 %left '^'
 %left '&'
@@ -90,7 +93,7 @@ use xp\compiler\ast\BracedExpressionNode;
 %nonassoc T_INSTANCEOF
 %right '~' T_INC T_DEC
 %right '['
-%right T_AS 
+%right T_AS
 %nonassoc T_NEW T_CLONE
 
 %token T_WORD 260
@@ -143,6 +146,7 @@ use xp\compiler\ast\BracedExpressionNode;
 %token T_IN 364
 %token T_BREAK 365
 %token T_CONTINUE 366
+%token T_YIELD 367
 
 %token T_IF 370
 %token T_ELSE 371
@@ -823,7 +827,16 @@ expression:
       }
     }
   | T_CLONE expression { 
-      $$= $yyLex->create(new CloneNode($2)); break;
+      $$= $yyLex->create(new CloneNode($2));
+    }
+  | T_YIELD {
+      $$= $yyLex->create(new YieldNode());
+    }
+  | T_YIELD expression {
+      $$= $yyLex->create(new YieldNode($2));
+    }
+  | T_YIELD expression ':' expression {
+      $$= $yyLex->create(new YieldNode($4, $2));
     }
   | expression T_AS paramtyperef { 
       $$= $yyLex->create(new CastNode(array_merge($3, array('expression' => $1)))); 

src/main/php/xp/compiler/Runner.class.php

@@ -47,7 +47,7 @@
  *     Adds path to source path (source path will equal classpath initially)
  *   </li>
  *   <li>-E [emitter]: 
- *     Use emitter, defaults to "php5.4"
+ *     Use emitter, defaults to "php5.5"
  *   </li>
  *   <li>-p [profile[,profile[,...]]]:
  *     Use compiler profiles (defaults to ["default"]) - xp/compiler/{profile}.xcp.ini
@@ -180,8 +180,8 @@ public static function main(array $args) {
     $manager->setSourcePaths(\xp::$classpath);
 
     // Handle arguments
-    $profiles= array('default');
-    $emitter= 'php5.4';
+    $profiles= ['default'];
+    $emitter= 'php5.5';
     $result= function($success) { return $success ? 0 : 1; };
     $files= array();
     $listener= new DefaultDiagnosticListener(Console::$out);

src/main/php/xp/compiler/ast/YieldNode.class.php

@@ -0,0 +1,23 @@
+<?php namespace xp\compiler\ast;
+
+/**
+ * The "yield" statement
+ */
+class YieldNode extends Node {
+  public $value= null;
+  public $key= null;
+
+  public function __construct($value= null, $key= null) {
+    $this->value= $value;
+    $this->key= $key;
+  }
+
+  /**
+   * Returns a hashcode
+   *
+   * @return  string
+   */
+  public function hashCode() {
+    return 'yield '.($this->key ? $this->key->hashCode().' => ' : '').($this->value ? $this->value->hashCode() : '');
+  }
+}

src/main/php/xp/compiler/emit/Emitter.class.php

@@ -681,6 +681,14 @@ protected abstract function emitReturn($b, $return);
    * @param   xp.compiler.ast.SilenceOperatorNode silenced
    */
   protected abstract function emitSilenceOperator($b, $silenced);
+
+  /**
+   * Emit a yield node
+   *
+   * @param   xp.compiler.emit.Buffer b
+   * @param   xp.compiler.ast.YieldNode yield
+   */
+  protected abstract function emitYield($b, $yield);
 
   /**
    * Emit a single node
@@ -742,7 +750,7 @@ protected function format($code, $message, Node $context= null) {
       $pos= $context->position;
     } else {                      // Try to determine last context node from backtrace
       $pos= array(0, 0);
-      foreach (create(new \lang\Throwable(null))->getStackTrace() as $element) {
+      foreach ((new \lang\Throwable(null))->getStackTrace() as $element) {
         if (
           'emit' == substr($element->method, 0, 4) &&
           sizeof($element->args) > 1 &&

src/main/php/xp/compiler/emit/php/Emitter.class.php

@@ -2429,6 +2429,16 @@ protected function emitSilenceOperator($b, $silenced) {
     $this->scope[0]->setType($silenced, $this->scope[0]->typeOf($silenced->expression));
   }
 
+  /**
+   * Emit a yield node
+   *
+   * @param   xp.compiler.emit.Buffer b
+   * @param   xp.compiler.ast.YieldNode yield
+   */
+  protected function emitYield($b, $yield) {
+    $this->error('V505', 'Yield not supported in '.$this->getClassName());
+  }
+
   /**
    * Emit all given nodes
    *

src/main/php/xp/compiler/emit/php/V55Emitter.class.php

@@ -0,0 +1,24 @@
+<?php namespace xp\compiler\emit\php;
+
+/**
+* Emits sourcecode using PHP 5.5 sourcecode
+ */
+class V55Emitter extends V54Emitter {
+
+  /**
+   * Emit a yield node
+   *
+   * @param   xp.compiler.emit.Buffer b
+   * @param   xp.compiler.ast.YieldNode yield
+   */
+  protected function emitYield($b, $yield) {
+    $b->append('yield ');
+    if ($yield->key) {
+      $this->emitOne($b, $yield->key);
+      $b->append(' => ');
+      $this->emitOne($b, $yield->value);
+    } else if ($yield->value) {
+      $this->emitOne($b, $yield->value);
+    }
+  }
+}

src/main/php/xp/compiler/syntax/php/Lexer.class.php

@@ -49,6 +49,7 @@ class Lexer extends \text\parser\generic\AbstractLexer {
       'while'         => Parser::T_WHILE,
       'break'         => Parser::T_BREAK,
       'continue'      => Parser::T_CONTINUE,
+      'yield'         => Parser::T_YIELD,
 
       'if'            => Parser::T_IF,
       'else'          => Parser::T_ELSE,