From 1a5e7e1bdd7ca9bf64bf396096c22ed08c1ae5b1 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Wed, 27 Mar 2024 13:32:06 +0100
Subject: [PATCH 01/15] Add support for pipelines with `|>` and `?|>`

---
 src/main/php/lang/ast/emit/PHP.class.php      | 40 ++++++++++
 .../ast/unittest/emit/PipelinesTest.class.php | 75 +++++++++++++++++++
 2 files changed, 115 insertions(+)
 create mode 100755 src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php

diff --git a/src/main/php/lang/ast/emit/PHP.class.php b/src/main/php/lang/ast/emit/PHP.class.php
index ac3d93a4..d86cdb7c 100755
--- a/src/main/php/lang/ast/emit/PHP.class.php
+++ b/src/main/php/lang/ast/emit/PHP.class.php
@@ -7,6 +7,8 @@
   ArrayLiteral,
   BinaryExpression,
   Block,
+  CallableExpression,
+  CallableNewExpression,
   Comment,
   Expression,
   InstanceExpression,
@@ -1129,6 +1131,44 @@ protected function emitNullsafeInstance($result, $instance) {
     $this->emitOne($result, $instance->member);
   }
 
+  protected function emitPipeTarget($result, $pipe, $argument) {
+
+    // $expr |> new T(...) => new T($expr)
+    if ($pipe->target instanceof CallableNewExpression) {
+      $pipe->target->type->arguments= [$argument];
+      $this->emitOne($result, $pipe->target->type);
+      $pipe->target->type->arguments= null;
+      return;
+    }
+
+    // $expr |> strtoupper(...) => strtoupper($expr)
+    // $expr |> fn($x) => $x * 2 => (fn($x) => $x * 2)($expr)
+    if ($pipe->target instanceof CallableExpression) {
+      $this->emitOne($result, $pipe->target->expression);
+    } else {
+      $result->out->write('(');
+      $this->emitOne($result, $pipe->target);
+      $result->out->write(')');
+    }
+
+    $result->out->write('(');
+    $this->emitOne($result, $argument);
+    $result->out->write(')');
+  }
+
+  protected function emitPipe($result, $pipe) {
+    $this->emitPipeTarget($result, $pipe, $pipe->expression);
+  }
+
+  protected function emitNullsafePipe($result, $pipe) {
+    $t= $result->temp();
+    $result->out->write('null===('.$t.'=');
+    $this->emitOne($result, $pipe->expression);
+    $result->out->write(')?null:');
+
+    $this->emitPipeTarget($result, $pipe, new Variable(substr($t, 1)));
+  }
+
   protected function emitUnpack($result, $unpack) {
     $result->out->write('...');
     $this->emitOne($result, $unpack->expression);
diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
new file mode 100755
index 00000000..7fa46a9f
--- /dev/null
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -0,0 +1,75 @@
+<?php namespace lang\ast\unittest\emit;
+
+use lang\IllegalStateException;
+use test\{Assert, Expect, Test, Values};
+
+class PipelinesTest extends EmittingTest {
+
+  #[Test]
+  public function pipe_to_callable() {
+    $r= $this->run('class %T {
+      public function run() {
+        return "test" |> strtoupper(...);
+      }
+    }');
+
+    Assert::equals('TEST', $r);
+  }
+
+  #[Test]
+  public function pipe_to_callable_new() {
+    $r= $this->run('class %T {
+      public function run() {
+        return "2024-03-27" |> new \util\Date(...);
+      }
+    }');
+
+    Assert::equals('2024-03-27', $r->toString('Y-m-d'));
+  }
+
+  #[Test]
+  public function pipe_to_callable_anonymous_new() {
+    $r= $this->run('class %T {
+      public function run() {
+        return "2024-03-27" |> new class(...) {
+          public function __construct(public string $value) { }
+        };
+      }
+    }');
+
+    Assert::equals('2024-03-27', $r->value);
+  }
+
+  #[Test]
+  public function pipe_to_closure() {
+    $r= $this->run('class %T {
+      public function run() {
+        return "test" |> fn($x) => $x.": OK";
+      }
+    }');
+
+    Assert::equals('test: OK', $r);
+  }
+
+  #[Test]
+  public function pipe_chain() {
+    $r= $this->run('class %T {
+      public function run() {
+        return " test " |> trim(...) |> strtoupper(...);
+      }
+    }');
+
+    Assert::equals('TEST', $r);
+  }
+
+  #[Test, Values([[null, null], ['test', 'TEST'], [' test ', 'TEST']])]
+  public function nullsafe_pipe($input, $expected) {
+    $r= $this->run('class %T {
+      public function run($arg) {
+        return $arg ?|> trim(...) ?|> strtoupper(...);
+      }
+    }', $input);
+
+    Assert::equals($expected, $r);
+  }
+}
\ No newline at end of file

From 196dfb9d055d2262e143045564d6aea1f83f9969 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Wed, 27 Mar 2024 13:37:47 +0100
Subject: [PATCH 02/15] QA: Remove unused imports

---
 src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
index 7fa46a9f..cff7cd90 100755
--- a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -1,7 +1,6 @@
 <?php namespace lang\ast\unittest\emit;
 
-use lang\IllegalStateException;
-use test\{Assert, Expect, Test, Values};
+use test\{Assert, Test, Values};
 
 class PipelinesTest extends EmittingTest {
 

From c016b6c3144f3db03613da88971e9e9cfdff40d6 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Wed, 27 Mar 2024 13:42:10 +0100
Subject: [PATCH 03/15] Add test ensuring the expression is only invoked once

---
 .../lang/ast/unittest/emit/PipelinesTest.class.php  | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
index cff7cd90..0b10220f 100755
--- a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -61,8 +61,19 @@ public function run() {
     Assert::equals('TEST', $r);
   }
 
-  #[Test, Values([[null, null], ['test', 'TEST'], [' test ', 'TEST']])]
+  #[Test, Values([[['test'], 'TEST'], [[], null]])]
   public function nullsafe_pipe($input, $expected) {
+    $r= $this->run('class %T {
+      public function run($arg) {
+        return array_shift($arg) ?|> strtoupper(...);
+      }
+    }', $input);
+
+    Assert::equals($expected, $r);
+  }
+
+  #[Test, Values([[null, null], ['test', 'TEST'], [' test ', 'TEST']])]
+  public function nullsafe_chain($input, $expected) {
     $r= $this->run('class %T {
       public function run($arg) {
         return $arg ?|> trim(...) ?|> strtoupper(...);

From 725e453642f22c9d744cf430fbf9da969c0ecc1c Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Wed, 27 Mar 2024 14:13:16 +0100
Subject: [PATCH 04/15] Add tests for a variety of callables

---
 .../ast/unittest/emit/PipelinesTest.class.php | 47 +++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
index 0b10220f..8e5dbeec 100755
--- a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -15,6 +15,53 @@ public function run() {
     Assert::equals('TEST', $r);
   }
 
+  #[Test]
+  public function pipe_to_variable() {
+    $r= $this->run('class %T {
+      public function run() {
+        $f= strtoupper(...);
+        return "test" |> $f;
+      }
+    }');
+
+    Assert::equals('TEST', $r);
+  }
+
+  #[Test]
+  public function pipe_to_callable_string() {
+    $r= $this->run('class %T {
+      public function run() {
+        return "test" |> "strtoupper";
+      }
+    }');
+
+    Assert::equals('TEST', $r);
+  }
+
+  #[Test]
+  public function pipe_to_callable_array() {
+    $r= $this->run('class %T {
+      public function toUpper($x) { return strtoupper($x); }
+
+      public function run() {
+        return "test" |> [$this, "toUpper"];
+      }
+    }');
+
+    Assert::equals('TEST', $r);
+  }
+
+  #[Test]
+  public function pipe_to_callable_without_all_args() {
+    $r= $this->run('class %T {
+      public function run() {
+        return "A&B" |> htmlspecialchars(...);
+      }
+    }');
+
+    Assert::equals('A&amp;B', $r);
+  }
+
   #[Test]
   public function pipe_to_callable_new() {
     $r= $this->run('class %T {

From 00d9658885f6b2e645eea1ca8571aa134e59c1c4 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Wed, 27 Mar 2024 15:09:38 +0100
Subject: [PATCH 05/15] Fix xp-framework/ast dependency

---
 composer.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/composer.json b/composer.json
index 303b7c68..af9cf190 100755
--- a/composer.json
+++ b/composer.json
@@ -8,7 +8,7 @@
   "require" : {
     "xp-framework/core": "^12.0 | ^11.6 | ^10.16",
     "xp-framework/reflection": "^3.0 | ^2.13",
-    "xp-framework/ast": "^11.0 | ^10.1",
+    "xp-framework/ast": "dev-feature/pipelines as 11.1.0",
     "php" : ">=7.4.0"
   },
   "require-dev" : {

From ff28975cf0a3c69756df61ef818e8f916c4092ed Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sat, 8 Feb 2025 09:59:48 +0100
Subject: [PATCH 06/15] Link to https://wiki.php.net/rfc/pipe-operator-v3

---
 .../ast/unittest/emit/PipelinesTest.class.php    | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
index 8e5dbeec..fdcb1231 100755
--- a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -2,6 +2,7 @@
 
 use test\{Assert, Test, Values};
 
+/** @see https://wiki.php.net/rfc/pipe-operator-v3 */
 class PipelinesTest extends EmittingTest {
 
   #[Test]
@@ -129,4 +130,19 @@ public function run($arg) {
 
     Assert::equals($expected, $r);
   }
+
+  #[Test]
+  public function rfc_example() {
+    $r= $this->run('class %T {
+      public function run() {
+        return "Hello World"
+          |> "htmlentities"
+          |> str_split(...)
+          |> fn($x) => array_map(strtoupper(...), $x)
+          |> fn($x) => array_filter($x, fn($v) => $v != "O")
+        ;
+      }
+    }');
+    Assert::equals(['H', 'E', 'L', 'L', ' ', 'W', 'R', 'L', 'D'], array_values($r));
+  }
 }
\ No newline at end of file

From a7c7d79949f628d15cfe1cb35d7cbaf4c30a0616 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sat, 8 Feb 2025 10:02:11 +0100
Subject: [PATCH 07/15] Test precedence, see
 https://wiki.php.net/rfc/pipe-operator-v3#precedence

---
 .../lang/ast/unittest/emit/PipelinesTest.class.php    | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
index fdcb1231..b18915a0 100755
--- a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -131,6 +131,17 @@ public function run($arg) {
     Assert::equals($expected, $r);
   }
 
+  #[Test]
+  public function precedence() {
+    $r= $this->run('class %T {
+      public function run() {
+        return "te"."st" |> strtoupper(...);
+      }
+    }');
+
+    Assert::equals('TEST', $r);
+  }
+
   #[Test]
   public function rfc_example() {
     $r= $this->run('class %T {

From 4357341f0cb254d8ff06bad5c05fbf576f9a6d8f Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sun, 18 May 2025 11:22:05 +0200
Subject: [PATCH 08/15] Fix pipeline execution order

---
 src/main/php/lang/ast/emit/PHP.class.php      |  44 +++--
 .../ast/unittest/emit/PipelinesTest.class.php | 166 +++++++++++++++++-
 2 files changed, 183 insertions(+), 27 deletions(-)

diff --git a/src/main/php/lang/ast/emit/PHP.class.php b/src/main/php/lang/ast/emit/PHP.class.php
index 01e3e15b..fc7256a4 100755
--- a/src/main/php/lang/ast/emit/PHP.class.php
+++ b/src/main/php/lang/ast/emit/PHP.class.php
@@ -1158,42 +1158,40 @@ protected function emitNullsafeInstance($result, $instance) {
     $this->emitOne($result, $instance->member);
   }
 
-  protected function emitPipeTarget($result, $pipe, $argument) {
-
-    // $expr |> new T(...) => new T($expr)
-    if ($pipe->target instanceof CallableNewExpression) {
-      $pipe->target->type->arguments= [$argument];
-      $this->emitOne($result, $pipe->target->type);
-      $pipe->target->type->arguments= null;
-      return;
-    }
-
-    // $expr |> strtoupper(...) => strtoupper($expr)
-    // $expr |> fn($x) => $x * 2 => (fn($x) => $x * 2)($expr)
-    if ($pipe->target instanceof CallableExpression) {
-      $this->emitOne($result, $pipe->target->expression);
+  protected function emitPipeTarget($result, $target, $arg) {
+    if ($target instanceof CallableNewExpression) {
+      $target->type->arguments= [new Variable(substr($arg, 1))];
+      $this->emitOne($result, $target->type);
+      $target->type->arguments= null;
+    } else if ($target instanceof CallableExpression) {
+      $this->emitOne($result, $target->expression);
+      $result->out->write('('.$arg.')');
     } else {
       $result->out->write('(');
-      $this->emitOne($result, $pipe->target);
-      $result->out->write(')');
+      $this->emitOne($result, $target);
+      $result->out->write(')('.$arg.')');
     }
-
-    $result->out->write('(');
-    $this->emitOne($result, $argument);
-    $result->out->write(')');
   }
 
   protected function emitPipe($result, $pipe) {
-    $this->emitPipeTarget($result, $pipe, $pipe->expression);
+
+    // $expr |> strtoupper(...) => [$arg= $expr, strtoupper($arg)][1]
+    $t= $result->temp();
+    $result->out->write('['.$t.'=');
+    $this->emitOne($result, $pipe->expression);
+    $result->out->write(',');
+    $this->emitPipeTarget($result, $pipe->target, $t);
+    $result->out->write('][1]');
   }
 
   protected function emitNullsafePipe($result, $pipe) {
+
+    // $expr ?|> strtoupper(...) => null === ($arg= $expr) ? null : strtoupper($arg)
     $t= $result->temp();
     $result->out->write('null===('.$t.'=');
     $this->emitOne($result, $pipe->expression);
     $result->out->write(')?null:');
-
-    $this->emitPipeTarget($result, $pipe, new Variable(substr($t, 1)));
+    $this->emitPipeTarget($result, $pipe->target, $t);
   }
 
   protected function emitUnpack($result, $unpack) {
diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
index b18915a0..43bfc290 100755
--- a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -1,6 +1,8 @@
 <?php namespace lang\ast\unittest\emit;
 
-use test\{Assert, Test, Values};
+use lang\Error;
+use test\verify\Runtime;
+use test\{Assert, Expect, Test, Values};
 
 /** @see https://wiki.php.net/rfc/pipe-operator-v3 */
 class PipelinesTest extends EmittingTest {
@@ -98,6 +100,24 @@ public function run() {
     Assert::equals('test: OK', $r);
   }
 
+  #[Test, Expect(Error::class)]
+  public function pipe_to_throw() {
+    $this->run('use lang\Error; class %T {
+      public function run() {
+        return "test" |> throw new Error("Test");
+      }
+    }');
+  }
+
+  #[Test, Expect(Error::class)]
+  public function pipe_to_missing() {
+    $this->run('class %T {
+      public function run() {
+        return "test" |> "__missing";
+      }
+    }');
+  }
+
   #[Test]
   public function pipe_chain() {
     $r= $this->run('class %T {
@@ -109,7 +129,7 @@ public function run() {
     Assert::equals('TEST', $r);
   }
 
-  #[Test, Values([[['test'], 'TEST'], [[], null]])]
+  #[Test, Values([[['test'], 'TEST'], [[''], ''], [[], null]])]
   public function nullsafe_pipe($input, $expected) {
     $r= $this->run('class %T {
       public function run($arg) {
@@ -120,7 +140,7 @@ public function run($arg) {
     Assert::equals($expected, $r);
   }
 
-  #[Test, Values([[null, null], ['test', 'TEST'], [' test ', 'TEST']])]
+  #[Test, Values([[null, null], ['', ''], ['test', 'TEST'], [' test ', 'TEST']])]
   public function nullsafe_chain($input, $expected) {
     $r= $this->run('class %T {
       public function run($arg) {
@@ -132,7 +152,7 @@ public function run($arg) {
   }
 
   #[Test]
-  public function precedence() {
+  public function concat_precedence() {
     $r= $this->run('class %T {
       public function run() {
         return "te"."st" |> strtoupper(...);
@@ -142,6 +162,54 @@ public function run() {
     Assert::equals('TEST', $r);
   }
 
+  #[Test]
+  public function addition_precedence() {
+    $r= $this->run('class %T {
+      public function run() {
+        return 5 + 2 |> fn($i) => $i * 2;
+      }
+    }');
+
+    Assert::equals(14, $r);
+  }
+
+  #[Test]
+  public function comparison_precedence() {
+    $r= $this->run('class %T {
+      public function run() {
+        return 5 |> fn($i) => $i * 2 === 10;
+      }
+    }');
+
+    Assert::true($r);
+  }
+
+  #[Test, Values([[0, 'even'], [1, 'odd'], [2, 'even']])]
+  public function ternary_precedence($arg, $expected) {
+    $r= $this->run('class %T {
+      public function run($arg) {
+        return $arg |> fn($i) => $i % 2 ? "odd" : "even";
+      }
+    }', $arg);
+
+    Assert::equals($expected, $r);
+  }
+
+  #[Test, Values([[0, 'root'], [1001, 'test'], [1002, '#unknown']])]
+  public function coalesce_precedence($arg, $expected) {
+    $r= $this->run('class %T {
+      private $users= [0 => "root", 1001 => "test"];
+
+      private function user($id) { return $this->users[$id] ?? null; }
+
+      public function run($arg) {
+        return $arg |> $this->user(...) ?? "#unknown";
+      }
+    }', $arg);
+
+    Assert::equals($expected, $r);
+  }
+
   #[Test]
   public function rfc_example() {
     $r= $this->run('class %T {
@@ -156,4 +224,94 @@ public function run() {
     }');
     Assert::equals(['H', 'E', 'L', 'L', ' ', 'W', 'R', 'L', 'D'], array_values($r));
   }
+
+  #[Test, Expect(Error::class), Runtime(php: '>=8.5.0')]
+  public function rejects_by_reference_functions() {
+    $this->run('class %T {
+      private function modify(&$arg) { $arg++; }
+
+      public function run() {
+        $val= 1;
+        return $val |> $this->modify(...);
+      }
+    }');
+  }
+
+  #[Test]
+  public function accepts_prefer_by_reference_functions() {
+    $r= $this->run('class %T {
+      public function run() {
+        return ["hello", "world"] |> array_multisort(...);
+      }
+    }');
+
+    Assert::true($r);
+  }
+
+  #[Test]
+  public function execution_order() {
+    $r= $this->run('class %T {
+      public function run() {
+        $invoked= [];
+
+        $first= function() use(&$invoked) { $invoked[]= "first"; return 1; };
+        $second= function() use(&$invoked) { $invoked[]= "second"; return false; };
+        $skipped= function() use(&$invoked) { $invoked[]= "skipped"; return $in; };
+        $third= function($in) use(&$invoked) { $invoked[]= "third"; return $in; };
+        $capture= function($result) use(&$invoked) { $invoked[]= $result; };
+
+        $first() |> ($second() ? $skipped : $third) |> $capture;
+        return $invoked;
+      }
+    }');
+
+    Assert::equals(['first', 'second', 'third', 1], $r);
+  }
+
+  #[Test]
+  public function interrupted_by_exception() {
+    $r= $this->run('use lang\Error; class %T {
+      public function run() {
+        $invoked= [];
+
+        $provide= function() use(&$invoked) { $invoked[]= "provide"; return 1; };
+        $transform= function($in) use(&$invoked) { $invoked[]= "transform"; return $in * 2; };
+        $throw= function() use(&$invoked) { $invoked[]= "throw"; throw new Error("Break"); };
+
+        try {
+          $provide() |> $transform |> $throw |> throw new Error("Unreachable");
+        } catch (Error $e) {
+          $invoked[]= $e->compoundMessage();
+        }
+        return $invoked;
+      }
+    }');
+
+    Assert::equals(['provide', 'transform', 'throw', 'Exception lang.Error (Break)'], $r);
+  }
+
+  #[Test]
+  public function generators() {
+    $r= $this->run('class %T {
+      private function range($lo, $hi) {
+        for ($i= $lo; $i <= $hi; $i++) {
+          yield $i;
+        }
+      }
+
+      private function map($fn) {
+        return function($it) use($fn) {
+          foreach ($it as $element) {
+            yield $fn($element);
+          }
+        };
+      }
+
+      public function run() {
+        return $this->range(1, 3) |> $this->map(fn($e) => $e + 1) |> iterator_to_array(...);
+      }
+    }');
+
+    Assert::equals([2, 3, 4], $r);
+  }
 }
\ No newline at end of file

From e05b5b13638323b1eba3a57e088a2b24b421f40c Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sun, 18 May 2025 11:54:00 +0200
Subject: [PATCH 09/15] Extract pipeline emulation into trait

Once php/php-src#17118 is merged, we can create a PHP 8.5 emitter which
does not include it and emits pipes natively
---
 .../lang/ast/emit/EmulatePipelines.class.php  | 48 +++++++++++++++++++
 src/main/php/lang/ast/emit/PHP.class.php      | 30 ++----------
 src/main/php/lang/ast/emit/PHP74.class.php    |  1 +
 src/main/php/lang/ast/emit/PHP80.class.php    |  1 +
 src/main/php/lang/ast/emit/PHP81.class.php    |  1 +
 src/main/php/lang/ast/emit/PHP82.class.php    |  1 +
 src/main/php/lang/ast/emit/PHP83.class.php    |  2 +-
 src/main/php/lang/ast/emit/PHP84.class.php    |  2 +-
 8 files changed, 59 insertions(+), 27 deletions(-)
 create mode 100755 src/main/php/lang/ast/emit/EmulatePipelines.class.php

diff --git a/src/main/php/lang/ast/emit/EmulatePipelines.class.php b/src/main/php/lang/ast/emit/EmulatePipelines.class.php
new file mode 100755
index 00000000..d101605c
--- /dev/null
+++ b/src/main/php/lang/ast/emit/EmulatePipelines.class.php
@@ -0,0 +1,48 @@
+<?php namespace lang\ast\emit;
+
+use lang\ast\nodes\{CallableExpression, CallableNewExpression, Variable};
+
+/**
+ * Emulates pipelines
+ *
+ * @see  https://wiki.php.net/rfc/pipe-operator-v3#precedence
+ * @test lang.ast.unittest.emit.PipelinesTest
+ */
+trait EmulatePipelines {
+
+  protected function emitPipeTarget($result, $target, $arg) {
+    if ($target instanceof CallableNewExpression) {
+      $target->type->arguments= [new Variable(substr($arg, 1))];
+      $this->emitOne($result, $target->type);
+      $target->type->arguments= null;
+    } else if ($target instanceof CallableExpression) {
+      $this->emitOne($result, $target->expression);
+      $result->out->write('('.$arg.')');
+    } else {
+      $result->out->write('(');
+      $this->emitOne($result, $target);
+      $result->out->write(')('.$arg.')');
+    }
+  }
+
+  protected function emitPipe($result, $pipe) {
+
+    // $expr |> strtoupper(...) => [$arg= $expr, strtoupper($arg)][1]
+    $t= $result->temp();
+    $result->out->write('['.$t.'=');
+    $this->emitOne($result, $pipe->expression);
+    $result->out->write(',');
+    $this->emitPipeTarget($result, $pipe->target, $t);
+    $result->out->write('][1]');
+  }
+
+  protected function emitNullsafePipe($result, $pipe) {
+
+    // $expr ?|> strtoupper(...) => null === ($arg= $expr) ? null : strtoupper($arg)
+    $t= $result->temp();
+    $result->out->write('null===('.$t.'=');
+    $this->emitOne($result, $pipe->expression);
+    $result->out->write(')?null:');
+    $this->emitPipeTarget($result, $pipe->target, $t);
+  }
+}
\ No newline at end of file
diff --git a/src/main/php/lang/ast/emit/PHP.class.php b/src/main/php/lang/ast/emit/PHP.class.php
index fc7256a4..584769e3 100755
--- a/src/main/php/lang/ast/emit/PHP.class.php
+++ b/src/main/php/lang/ast/emit/PHP.class.php
@@ -1158,40 +1158,20 @@ protected function emitNullsafeInstance($result, $instance) {
     $this->emitOne($result, $instance->member);
   }
 
-  protected function emitPipeTarget($result, $target, $arg) {
-    if ($target instanceof CallableNewExpression) {
-      $target->type->arguments= [new Variable(substr($arg, 1))];
-      $this->emitOne($result, $target->type);
-      $target->type->arguments= null;
-    } else if ($target instanceof CallableExpression) {
-      $this->emitOne($result, $target->expression);
-      $result->out->write('('.$arg.')');
-    } else {
-      $result->out->write('(');
-      $this->emitOne($result, $target);
-      $result->out->write(')('.$arg.')');
-    }
-  }
-
   protected function emitPipe($result, $pipe) {
-
-    // $expr |> strtoupper(...) => [$arg= $expr, strtoupper($arg)][1]
-    $t= $result->temp();
-    $result->out->write('['.$t.'=');
     $this->emitOne($result, $pipe->expression);
-    $result->out->write(',');
-    $this->emitPipeTarget($result, $pipe->target, $t);
-    $result->out->write('][1]');
+    $result->out->write('|>');
+    $this->emitOne($result, $pipe->target);
   }
 
   protected function emitNullsafePipe($result, $pipe) {
 
-    // $expr ?|> strtoupper(...) => null === ($arg= $expr) ? null : strtoupper($arg)
+    // $expr ?|> strtoupper(...) => null === ($t= $expr) ? null : $t |> strtoupper(...)
     $t= $result->temp();
     $result->out->write('null===('.$t.'=');
     $this->emitOne($result, $pipe->expression);
-    $result->out->write(')?null:');
-    $this->emitPipeTarget($result, $pipe->target, $t);
+    $result->out->write(')?null:'.$t.'|>');
+    $this->emitOne($result, $pipe->target);
   }
 
   protected function emitUnpack($result, $unpack) {
diff --git a/src/main/php/lang/ast/emit/PHP74.class.php b/src/main/php/lang/ast/emit/PHP74.class.php
index 6f97959c..d8feaec8 100755
--- a/src/main/php/lang/ast/emit/PHP74.class.php
+++ b/src/main/php/lang/ast/emit/PHP74.class.php
@@ -14,6 +14,7 @@ class PHP74 extends PHP {
     AttributesAsComments,
     CallablesAsClosures,
     ChainScopeOperators,
+    EmulatePipelines,
     MatchAsTernaries,
     NonCapturingCatchVariables,
     NullsafeAsTernaries,
diff --git a/src/main/php/lang/ast/emit/PHP80.class.php b/src/main/php/lang/ast/emit/PHP80.class.php
index db83e745..02c67c29 100755
--- a/src/main/php/lang/ast/emit/PHP80.class.php
+++ b/src/main/php/lang/ast/emit/PHP80.class.php
@@ -21,6 +21,7 @@ class PHP80 extends PHP {
   use
     ArrayUnpackUsingMerge,
     CallablesAsClosures,
+    EmulatePipelines,
     OmitConstantTypes,
     ReadonlyClasses,
     RewriteBlockLambdaExpressions,
diff --git a/src/main/php/lang/ast/emit/PHP81.class.php b/src/main/php/lang/ast/emit/PHP81.class.php
index f93b4969..f0062593 100755
--- a/src/main/php/lang/ast/emit/PHP81.class.php
+++ b/src/main/php/lang/ast/emit/PHP81.class.php
@@ -20,6 +20,7 @@
  */
 class PHP81 extends PHP {
   use
+    EmulatePipelines,
     RewriteBlockLambdaExpressions,
     RewriteDynamicClassConstants,
     RewriteStaticVariableInitializations,
diff --git a/src/main/php/lang/ast/emit/PHP82.class.php b/src/main/php/lang/ast/emit/PHP82.class.php
index 89fa9cbd..c8da1649 100755
--- a/src/main/php/lang/ast/emit/PHP82.class.php
+++ b/src/main/php/lang/ast/emit/PHP82.class.php
@@ -20,6 +20,7 @@
  */
 class PHP82 extends PHP {
   use
+    EmulatePipelines,
     RewriteBlockLambdaExpressions,
     RewriteDynamicClassConstants,
     RewriteStaticVariableInitializations,
diff --git a/src/main/php/lang/ast/emit/PHP83.class.php b/src/main/php/lang/ast/emit/PHP83.class.php
index 7c7293b2..06879d88 100755
--- a/src/main/php/lang/ast/emit/PHP83.class.php
+++ b/src/main/php/lang/ast/emit/PHP83.class.php
@@ -18,7 +18,7 @@
  * @see  https://wiki.php.net/rfc#php_83
  */
 class PHP83 extends PHP {
-  use RewriteBlockLambdaExpressions, RewriteProperties;
+  use EmulatePipelines, RewriteBlockLambdaExpressions, RewriteProperties;
 
   public $targetVersion= 80300;
 
diff --git a/src/main/php/lang/ast/emit/PHP84.class.php b/src/main/php/lang/ast/emit/PHP84.class.php
index 71379f30..a9083a8f 100755
--- a/src/main/php/lang/ast/emit/PHP84.class.php
+++ b/src/main/php/lang/ast/emit/PHP84.class.php
@@ -18,7 +18,7 @@
  * @see  https://wiki.php.net/rfc#php_84
  */
 class PHP84 extends PHP {
-  use RewriteBlockLambdaExpressions;
+  use EmulatePipelines, RewriteBlockLambdaExpressions;
 
   public $targetVersion= 80400;
 

From 1c5583f420720d73f0ace3f411d58ac8217e36b3 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sun, 18 May 2025 11:55:49 +0200
Subject: [PATCH 10/15] QA: Remove unused imports

---
 src/main/php/lang/ast/emit/PHP.class.php | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/main/php/lang/ast/emit/PHP.class.php b/src/main/php/lang/ast/emit/PHP.class.php
index 584769e3..56d0be09 100755
--- a/src/main/php/lang/ast/emit/PHP.class.php
+++ b/src/main/php/lang/ast/emit/PHP.class.php
@@ -7,8 +7,6 @@
   ArrayLiteral,
   BinaryExpression,
   Block,
-  CallableExpression,
-  CallableNewExpression,
   Comment,
   Expression,
   InstanceExpression,

From 93e033fdb74940312e4b7ae16df9fa17ab204105 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sun, 18 May 2025 11:55:49 +0200
Subject: [PATCH 11/15] QA: Document null-safe pipe operator [skip ci]

---
 src/main/php/lang/ast/emit/EmulatePipelines.class.php | 5 +++--
 src/main/php/lang/ast/emit/PHP.class.php              | 2 --
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/main/php/lang/ast/emit/EmulatePipelines.class.php b/src/main/php/lang/ast/emit/EmulatePipelines.class.php
index d101605c..828f3829 100755
--- a/src/main/php/lang/ast/emit/EmulatePipelines.class.php
+++ b/src/main/php/lang/ast/emit/EmulatePipelines.class.php
@@ -3,9 +3,10 @@
 use lang\ast\nodes\{CallableExpression, CallableNewExpression, Variable};
 
 /**
- * Emulates pipelines
+ * Emulates pipelines / the pipe operator, including a null-safe version.
  *
- * @see  https://wiki.php.net/rfc/pipe-operator-v3#precedence
+ * @see  https://wiki.php.net/rfc/pipe-operator-v3
+ * @see  https://externals.io/message/107661#107670
  * @test lang.ast.unittest.emit.PipelinesTest
  */
 trait EmulatePipelines {
diff --git a/src/main/php/lang/ast/emit/PHP.class.php b/src/main/php/lang/ast/emit/PHP.class.php
index 584769e3..56d0be09 100755
--- a/src/main/php/lang/ast/emit/PHP.class.php
+++ b/src/main/php/lang/ast/emit/PHP.class.php
@@ -7,8 +7,6 @@
   ArrayLiteral,
   BinaryExpression,
   Block,
-  CallableExpression,
-  CallableNewExpression,
   Comment,
   Expression,
   InstanceExpression,

From 55fc0bd12b93bbd529c1724273e396c738d58f87 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sun, 18 May 2025 13:14:15 +0200
Subject: [PATCH 12/15] Add more tests for operator precedence

---
 .../ast/unittest/emit/PipelinesTest.class.php | 27 +++++++++-
 .../ast/unittest/emit/TernaryTest.class.php   | 53 ++++++++++++++++++-
 2 files changed, 76 insertions(+), 4 deletions(-)

diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
index 43bfc290..27735487 100755
--- a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -155,7 +155,7 @@ public function run($arg) {
   public function concat_precedence() {
     $r= $this->run('class %T {
       public function run() {
-        return "te"."st" |> strtoupper(...);
+        return "te" . "st" |> strtoupper(...);
       }
     }');
 
@@ -187,8 +187,31 @@ public function run() {
   #[Test, Values([[0, 'even'], [1, 'odd'], [2, 'even']])]
   public function ternary_precedence($arg, $expected) {
     $r= $this->run('class %T {
+
+      private function odd($n) { return $n % 2; }
+
+      public function run($arg) {
+        return $arg |> $this->odd(...) ? "odd" : "even";
+      }
+    }', $arg);
+
+    Assert::equals($expected, $r);
+  }
+
+  #[Test, Values([[0, '(empty)'], [1, 'one element'], [2, '2 elements']])]
+  public function short_ternary_precedence($arg, $expected) {
+    $r= $this->run('class %T {
+
+      private function number($n) {
+        return match ($n) {
+          0 => null,
+          1 => "one element",
+          default => "{$n} elements"
+        };
+      }
+
       public function run($arg) {
-        return $arg |> fn($i) => $i % 2 ? "odd" : "even";
+        return $arg |> $this->number(...) ?: "(empty)";
       }
     }', $arg);
 
diff --git a/src/test/php/lang/ast/unittest/emit/TernaryTest.class.php b/src/test/php/lang/ast/unittest/emit/TernaryTest.class.php
index 39e9eb13..b0d7b133 100755
--- a/src/test/php/lang/ast/unittest/emit/TernaryTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/TernaryTest.class.php
@@ -56,12 +56,61 @@ public function run($value) {
   #[Test, Values(eval: '[["."], [new Path(".")]]')]
   public function with_instanceof($value) {
     Assert::equals(new Path('.'), $this->run(
-      'class %T {
+      'use io\\Path; class %T {
         public function run($value) {
-          return $value instanceof \\io\\Path ? $value : new \\io\\Path($value);
+          return $value instanceof Path ? $value : new Path($value);
         }
       }',
       $value
     ));
   }
+
+  #[Test, Values(['"te" . "st"', '1 + 2', '1 || 0', '2 ?? 1', '1 | 2', '4 === strlen("Test")'])]
+  public function precedence($lhs) {
+    Assert::equals('OK', $this->run(
+      'class %T {
+        public function run() {
+          return '.$lhs.'? "OK" : "Error";
+        }
+      }'
+    ));
+  }
+
+  #[Test]
+  public function assignment_precedence() {
+    Assert::equals(['OK', 'OK'], $this->run(
+      'class %T {
+        public function run() {
+          return [$a= 1 ? "OK" : "Error", $a];
+        }
+      }'
+    ));
+  }
+
+  #[Test]
+  public function yield_precedence() {
+    Assert::equals(['OK', null], iterator_to_array($this->run(
+      'class %T {
+        public function run() {
+          yield (yield 1 ? "OK" : "Error");
+        }
+      }'
+    )));
+  }
+
+  /** @see https://www.php.net/manual/en/language.operators.comparison.php#language.operators.comparison.ternary */
+  #[Test]
+  public function chaining_short_ternaries() {
+    Assert::equals([1, 2, 3], $this->run(
+      'class %T {
+        public function run() {
+          return [
+            0 ?: 1 ?: 2 ?: 3,
+            0 ?: 0 ?: 2 ?: 3,
+            0 ?: 0 ?: 0 ?: 3,
+          ];
+        }
+      }'
+    ));
+  }
 }
\ No newline at end of file

From a7b48e1787d68110a6db6f65f45df33e22d6fd71 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sun, 18 May 2025 13:21:33 +0200
Subject: [PATCH 13/15] Verify missing argument

---
 .../lang/ast/unittest/emit/PipelinesTest.class.php    | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
index 27735487..6d017ef7 100755
--- a/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
+++ b/src/test/php/lang/ast/unittest/emit/PipelinesTest.class.php
@@ -110,7 +110,7 @@ public function run() {
   }
 
   #[Test, Expect(Error::class)]
-  public function pipe_to_missing() {
+  public function missing_function() {
     $this->run('class %T {
       public function run() {
         return "test" |> "__missing";
@@ -118,6 +118,15 @@ public function run() {
     }');
   }
 
+  #[Test, Expect(Error::class)]
+  public function missing_argument() {
+    $this->run('class %T {
+      public function run() {
+        return 5 |> fn($a, $b) => $a * $b;
+      }
+    }');
+  }
+
   #[Test]
   public function pipe_chain() {
     $r= $this->run('class %T {

From a259b31ec458215764d40b2c75d14dcf66882c88 Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Sun, 18 May 2025 13:46:48 +0200
Subject: [PATCH 14/15] QA: Add `@test` references

---
 src/main/php/lang/ast/emit/PHP83.class.php | 1 +
 src/main/php/lang/ast/emit/PHP84.class.php | 1 +
 2 files changed, 2 insertions(+)

diff --git a/src/main/php/lang/ast/emit/PHP83.class.php b/src/main/php/lang/ast/emit/PHP83.class.php
index 06879d88..101ed9f1 100755
--- a/src/main/php/lang/ast/emit/PHP83.class.php
+++ b/src/main/php/lang/ast/emit/PHP83.class.php
@@ -15,6 +15,7 @@
 /**
  * PHP 8.3 syntax
  *
+ * @test lang.ast.unittest.emit.PHP83Test
  * @see  https://wiki.php.net/rfc#php_83
  */
 class PHP83 extends PHP {
diff --git a/src/main/php/lang/ast/emit/PHP84.class.php b/src/main/php/lang/ast/emit/PHP84.class.php
index a9083a8f..54c0face 100755
--- a/src/main/php/lang/ast/emit/PHP84.class.php
+++ b/src/main/php/lang/ast/emit/PHP84.class.php
@@ -15,6 +15,7 @@
 /**
  * PHP 8.4 syntax
  *
+ * @test lang.ast.unittest.emit.PHP84Test
  * @see  https://wiki.php.net/rfc#php_84
  */
 class PHP84 extends PHP {

From d309fea6308aa8093070c25c7260f48f54249cae Mon Sep 17 00:00:00 2001
From: Timm Friebe <thekid@thekid.de>
Date: Wed, 28 May 2025 21:28:54 +0200
Subject: [PATCH 15/15] Use AST library release version

---
 composer.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/composer.json b/composer.json
index ad441966..4ce18abd 100755
--- a/composer.json
+++ b/composer.json
@@ -8,7 +8,7 @@
   "require" : {
     "xp-framework/core": "^12.0 | ^11.6 | ^10.16",
     "xp-framework/reflection": "^3.2 | ^2.15",
-    "xp-framework/ast": "dev-feature/pipelines as 11.6.0",
+    "xp-framework/ast": "^11.6",
     "php" : ">=7.4.0"
   },
   "require-dev" : {