Upgrade to xphp v0.2.0 turbofish instantiation syntax

README.md

@@ -174,7 +174,7 @@ when any `.xphp` source changes. No separate `xphp:compile` step is needed.
   generated `XPHP\Generated\…` namespace. Write `\App\Finder\SourceInterface`, not a
   `use`d `SourceInterface`.
 - **You don't need a call site.** A generic that's only injected is never written as
-  `new Foo<Bar>()` anywhere, yet monomorphization is usage-driven. The bundle bridges
+  `new Foo::<Bar>()` anywhere, yet monomorphization is usage-driven. The bundle bridges
   this by synthesizing a throwaway instantiation for each declared binding at compile
   time (transparent; cleaned up afterwards). *(Stopgap: a future xphp release may
   accept specialization roots directly.)*

composer.json

@@ -24,11 +24,11 @@
     },
     "require": {
         "php": "^8.4.0",
-        "xphp-lang/xphp": "^0.1",
         "symfony/config": "^8.0",
         "symfony/console": "^8.0",
         "symfony/dependency-injection": "^8.0",
-        "symfony/http-kernel": "^8.0"
+        "symfony/http-kernel": "^8.0",
+        "xphp-lang/xphp": "^v0.2.0"
     },
     "require-dev": {
         "symfony/framework-bundle": "^8.0",

demo/README.md

@@ -14,7 +14,7 @@ src/
 ├── Command/DemoCommand.php   # handwritten PHP — calls into the compiled Catalog
 ├── Models/Plastic.php        # handwritten PHP — left untouched by the build
 ├── Containers/Box.xphp       # generic template  class Box<T>
-├── Demo/Catalog.xphp         # uses new Box<Plastic>()  (so it must be .xphp)
+├── Demo/Catalog.xphp         # uses new Box::<Plastic>()  (so it must be .xphp)
 └── Kernel.php
 ```
 

demo/src/Demo/Catalog.xphp

@@ -8,7 +8,7 @@ use App\Containers\Box;
 use App\Models\Plastic;
 
 /**
- * Exercises the generic. Because it instantiates `new Box<Plastic>()`, this file
+ * Exercises the generic. Because it instantiates `new Box::<Plastic>()`, this file
  * must be .xphp — the compiler rewrites those call sites to the concrete
  * XPHP\Generated\App\Containers\Box\T_<hash> classes. The public API
  * (`colors()`, `boxClass()`) is plain PHP, so handwritten code can call it
@@ -21,10 +21,10 @@ final class Catalog
      */
     public function colors(): array
     {
-        $red = new Box<Plastic>();
+        $red = new Box::<Plastic>();
         $red->set(new Plastic('red'));
 
-        $blue = new Box<Plastic>();
+        $blue = new Box::<Plastic>();
         $blue->set(new Plastic('blue'));
 
         return [$red->get()->color, $blue->get()->color];
@@ -36,7 +36,7 @@ final class Catalog
      */
     public function boxClass(): string
     {
-        $box = new Box<Plastic>();
+        $box = new Box::<Plastic>();
 
         return $box::class;
     }

src/Compiler/XphpCompiler.php

@@ -108,10 +108,10 @@ private function runCompiler(): string
      * Monomorphization is usage-driven: the transpiler only emits a `T_<hash>`
      * specialization where source actually instantiates `Foo<Bar>`. A generic that is
      * only declared as a DI service (and injected via an interface) is never written
-     * as `new Foo<Bar>()` anywhere, so its specialization would never be generated.
+     * as `new Foo::<Bar>()` anywhere, so its specialization would never be generated.
      *
      * As a stopgap we synthesize a throwaway `.xphp` file containing one
-     * `new Template<Args>();` per declared root, dropped into the source set so the
+     * `new Template::<Args>();` per declared root, dropped into the source set so the
      * transpiler treats it as a usage. The rewritten copy that lands in the target dir
      * is dead code (it is never autoloaded — the file declares no class) and is removed
      * by {@see removeRootsArtifacts()} along with the source file.
@@ -127,12 +127,31 @@ private function writeRootsFile(): void
 
         $lines = ['<?php', '', '// Auto-generated by xphp-symfony-bundle; safe to delete.'];
         foreach ($this->roots as $root) {
-            $lines[] = sprintf('new %s();', $root);
+            $lines[] = sprintf('new %s();', self::toTurbofish($root));
         }
 
         file_put_contents($dir . \DIRECTORY_SEPARATOR . 'roots.xphp', implode("\n", $lines) . "\n");
     }
 
+    /**
+     * Turn a canonical generic-instantiation expression (`Foo\Bar<Baz>`) into the
+     * call-site turbofish form xphp expects (`Foo\Bar::<Baz>`). xphp >= 0.2 requires
+     * the `::<…>` operator at instantiation sites — bare `new Foo<Baz>()` is now a
+     * parse error (`Foo < Baz` is ambiguous with comparison). Only the outermost
+     * `<` is the call site; nested type arguments keep their plain `<…>` form. A root
+     * with no type arguments becomes an empty turbofish (`Foo::<>`) so an
+     * all-defaulted template still triggers specialization.
+     */
+    private static function toTurbofish(string $canonical): string
+    {
+        $pos = strpos($canonical, '<');
+        if ($pos === false) {
+            return $canonical . '::<>';
+        }
+
+        return substr($canonical, 0, $pos) . '::' . substr($canonical, $pos);
+    }
+
     private function removeRootsArtifacts(): void
     {
         if ($this->roots === []) {