From dd1ff7b2bf0d27ce6da988a52a8d0dab71017023 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marcial=20Gai=C3=9Fert?= <uni@gaisseml.de>
Date: Tue, 13 May 2025 11:22:55 +0200
Subject: [PATCH 1/3] Add ControlAt[T] and loop[T] for control with argument

---
 examples/stdlib/control.check  |  2 ++
 examples/stdlib/control.effekt | 41 ++++++++++++++++++++++++++++++++++
 libraries/common/effekt.effekt | 11 +++++++++
 3 files changed, 54 insertions(+)
 create mode 100644 examples/stdlib/control.check
 create mode 100644 examples/stdlib/control.effekt

diff --git a/examples/stdlib/control.check b/examples/stdlib/control.check
new file mode 100644
index 000000000..c6e7924dc
--- /dev/null
+++ b/examples/stdlib/control.check
@@ -0,0 +1,2 @@
+5
+Some(-1)
\ No newline at end of file
diff --git a/examples/stdlib/control.effekt b/examples/stdlib/control.effekt
new file mode 100644
index 000000000..84f06b39a
--- /dev/null
+++ b/examples/stdlib/control.effekt
@@ -0,0 +1,41 @@
+
+type Term {
+  Add(x: Int, k: Term)
+  Return(v: Int)
+}
+
+def interp(t: Term): Int = {
+  var st = t
+  var pre = 0
+  loop{ {l} =>
+    st match {
+      case Add(x, k) => 
+        pre = pre + x
+        st = k
+      case Return(v) => l.break(pre + v)
+    }
+  }
+}
+
+def ctl_min(l: List[Int]): Option[Int] = {
+  var c_min = None()
+  var c_l = l
+  loop{ {l} =>
+    c_l match {
+      case Nil() => l.break()
+      case Cons(x, k) and c_min is None() =>
+        c_min = Some(x)
+        c_l = k
+      case Cons(x, k) and c_min is Some(m) and x < m => 
+        c_min = Some(x)
+        c_l = k
+      case Cons(x, k) => c_l = k
+    }
+  }
+  c_min
+}
+
+def main() = {
+  println(interp(Add(2, Add(3, Return(0)))))
+  println(ctl_min(Cons(0, Cons(1, Cons(-1, Nil())))))
+}
\ No newline at end of file
diff --git a/libraries/common/effekt.effekt b/libraries/common/effekt.effekt
index 1a73cb767..a43a414f3 100644
--- a/libraries/common/effekt.effekt
+++ b/libraries/common/effekt.effekt
@@ -722,6 +722,10 @@ interface Control {
   def break(): Unit
   def continue(): Unit
 }
+interface ControlAt[T] {
+  def break(t: T): Unit
+  def continue(): Unit
+}
 
 def loop { f: () => Unit }: Unit = {
   def go(): Unit = { f(); go() }
@@ -735,6 +739,13 @@ def loop { f: {Control} => Unit }: Unit = try {
   def break() = ()
   def continue() = loop { f }
 }
+def loop[T] { f: {ControlAt[T]} => Unit }: T = try {
+  def go(): T = { f{label}; go() }
+  go()
+} with label: ControlAt[T] {
+  def break(v) = v
+  def continue() = loop{f}
+}
 
 /// Calls provided action repeatedly. `start` is inclusive, `end` is not.
 def each(start: Int, end: Int) { action: (Int) => Unit } = {

From 819ead44c31b1976312c7be404bc4085c1d20c54 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marcial=20Gai=C3=9Fert?= <uni@gaisseml.de>
Date: Tue, 13 May 2025 11:27:13 +0200
Subject: [PATCH 2/3] Add test for only continue, restructure

---
 examples/stdlib/control.effekt | 12 ++++++++++++
 libraries/common/effekt.effekt | 10 ++++++----
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/examples/stdlib/control.effekt b/examples/stdlib/control.effekt
index 84f06b39a..ed24d8a0d 100644
--- a/examples/stdlib/control.effekt
+++ b/examples/stdlib/control.effekt
@@ -35,7 +35,19 @@ def ctl_min(l: List[Int]): Option[Int] = {
   c_min
 }
 
+effect exit(): Unit
+def nobreak(): Unit = {
+  var x = 12
+  try{
+    loop{ {l} =>
+      do exit()
+      l.continue()
+    }
+  } with exit { () => () }
+}
+
 def main() = {
   println(interp(Add(2, Add(3, Return(0)))))
   println(ctl_min(Cons(0, Cons(1, Cons(-1, Nil())))))
+  println(nobreak())
 }
\ No newline at end of file
diff --git a/libraries/common/effekt.effekt b/libraries/common/effekt.effekt
index a43a414f3..3e74cc4fa 100644
--- a/libraries/common/effekt.effekt
+++ b/libraries/common/effekt.effekt
@@ -722,10 +722,6 @@ interface Control {
   def break(): Unit
   def continue(): Unit
 }
-interface ControlAt[T] {
-  def break(t: T): Unit
-  def continue(): Unit
-}
 
 def loop { f: () => Unit }: Unit = {
   def go(): Unit = { f(); go() }
@@ -739,6 +735,12 @@ def loop { f: {Control} => Unit }: Unit = try {
   def break() = ()
   def continue() = loop { f }
 }
+
+interface ControlAt[T] {
+  def break(t: T): Unit
+  def continue(): Unit
+}
+
 def loop[T] { f: {ControlAt[T]} => Unit }: T = try {
   def go(): T = { f{label}; go() }
   go()

From daad7c68f23d70e010c3754a069447b73a4fd69d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marcial=20Gai=C3=9Fert?= <github@gaisseml.de>
Date: Tue, 13 May 2025 11:56:41 +0200
Subject: [PATCH 3/3] Fix check file

---
 examples/stdlib/control.check | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/examples/stdlib/control.check b/examples/stdlib/control.check
index c6e7924dc..87dc9916c 100644
--- a/examples/stdlib/control.check
+++ b/examples/stdlib/control.check
@@ -1,2 +1,3 @@
 5
-Some(-1)
\ No newline at end of file
+Some(-1)
+()
\ No newline at end of file