Initial proof of concept

Author: thekid

src/main/php/lang/ast/Result.class.php

@@ -1,12 +1,15 @@
 <?php namespace lang\ast;
 
+use lang\ast\types\{Declaration, Reflection};
+
 class Result {
   public $out;
   public $codegen;
   public $line= 1;
   public $meta= [];
   public $locals= [];
   public $stack= [];
+  public $type= [];
 
   /**
    * Starts a result stream, including a preamble
@@ -28,4 +31,20 @@ public function __construct($out, $preamble= '<?php ') {
   public function temp() {
     return '$'.$this->codegen->symbol();
   }
+
+  /**
+   * Looks up a given type 
+   *
+   * @param  string $type
+   * @return lang.ast.types.Type
+   */
+  public function lookup($type) {
+    if ('self' === $type || 'static' === $type || $type === $this->type[0]->name) {
+      return new Declaration($this->type[0], $this);
+    } else if ('parent' === $type) {
+      return $this->lookup($this->type[0]->parent);
+    } else {
+      return new Reflection($type);
+    }
+  }
 }

src/main/php/lang/ast/emit/PHP.class.php

@@ -350,6 +350,7 @@ protected function emitLambda($result, $lambda) {
   }
 
   protected function emitClass($result, $class) {
+    array_unshift($result->type, $class);
     array_unshift($result->meta, []);
     $result->locals= [[], []];
 
@@ -373,6 +374,7 @@ protected function emitClass($result, $class) {
     $this->emitInitializations($result, $result->locals[0]);
     $this->emitMeta($result, $class->name, $class->annotations, $class->comment);
     $result->out->write('}} '.$class->name.'::__init();');
+    array_shift($result->type);
   }
 
   /** Stores lowercased, unnamespaced name in annotations for BC reasons! */
@@ -909,6 +911,8 @@ protected function emitScope($result, $scope) {
       $result->out->write(')?'.$t.'::');
       $this->emitOne($result, $scope->member);
       $result->out->write(':null');
+    } else if ($scope->member instanceof Literal && '$enum' === $result->lookup($scope->type)->kind()) {
+      $result->out->write($scope->type.'::$'.$scope->member->expression);
     } else {
       $result->out->write($scope->type.'::');
       $this->emitOne($result, $scope->member);

src/test/php/lang/ast/unittest/emit/MembersTest.class.php

@@ -171,6 +171,19 @@ public function run() {
     Assert::equals('MON', $r);
   }
 
+  #[Test]
+  public function allow_constant_syntax_for_members() {
+    $r= $this->run('use lang\{Enum, CommandLine}; class <T> extends Enum {
+      public static $MON, $TUE, $WED, $THU, $FRI, $SAT, $SUN;
+
+      public function run() {
+        return [self::MON->name(), <T>::TUE->name(), CommandLine::WINDOWS->name()];
+      }
+    }');
+
+    Assert::equals(['MON', 'TUE', 'WINDOWS'], $r);
+  }
+
   #[Test]
   public function method_with_static() {
     $r= $this->run('class <T> {