From 10168d8ee4678478adaf653d771afcf7f2ef31a3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Mon, 1 Dec 2025 13:25:08 +0100
Subject: [PATCH 01/11] Use TestRenamer before showing core to humans

---
 .../test/scala/effekt/core/ReparseTests.scala |  2 +-
 .../scala/effekt/core/TestRenamerTests.scala  | 62 +++++++++----------
 .../scala/effekt/core/PrettyPrinter.scala     |  5 ++
 .../main}/scala/effekt/core/TestRenamer.scala | 14 ++++-
 .../effekt/generator/chez/ChezScheme.scala    |  2 +-
 .../effekt/generator/chez/ChezSchemeCPS.scala |  4 +-
 .../effekt/generator/js/JavaScript.scala      |  4 +-
 .../scala/effekt/generator/llvm/LLVM.scala    |  2 +-
 8 files changed, 54 insertions(+), 41 deletions(-)
 rename effekt/{jvm/src/test => shared/src/main}/scala/effekt/core/TestRenamer.scala (95%)

diff --git a/effekt/jvm/src/test/scala/effekt/core/ReparseTests.scala b/effekt/jvm/src/test/scala/effekt/core/ReparseTests.scala
index a7dea5dbaa..44edb7972e 100644
--- a/effekt/jvm/src/test/scala/effekt/core/ReparseTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/core/ReparseTests.scala
@@ -87,7 +87,7 @@ class ReparseTests extends CoreTests {
     }
     val reparsedRenamed = renamer(reparsed)
     val reparsedPrinted = core.PrettyPrinter.format(reparsedRenamed).layout
-    val expectedPrinted = core.PrettyPrinter.format(expectedRenamed).layout
+    val expectedPrinted = printed
     assertEquals(reparsedPrinted, expectedPrinted)
   }
 
diff --git a/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala b/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
index d867a14f5f..8df6d4c907 100644
--- a/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
@@ -12,7 +12,7 @@ class TestRenamerTests extends CoreTests {
                       names: Names = Names(defaultNames))(using munit.Location) = {
     val pInput = parse(input, "input", names)
     val pExpected = parse(renamed, "expected", names)
-    val renamer = new TestRenamer(names, "renamed") // use "renamed" as prefix so we can refer to it
+    val renamer = new TestRenamer(names, "_renamed_") // use "renamed" as prefix so we can refer to it
     val obtained = renamer(pInput)
     val obtainedPrinted = effekt.core.PrettyPrinter.format(obtained).layout
     val expectedPrinted = effekt.core.PrettyPrinter.format(pExpected).layout
@@ -31,7 +31,7 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |def renamed0() = {
+        |def _renamed_0() = {
         |  return (bar: (Int) => Int @ {})(baz: Int)
         |}
         |""".stripMargin
@@ -51,11 +51,11 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |def renamed0() = {
-        |  val renamed1: Int = {
-        |    renamed0: (Int) => Int @ {}(4)
+        |def foo_renamed_0() = {
+        |  val x_renamed_1: Int = {
+        |    foo_renamed_0: (Int) => Int @ {}(4)
         |  };
-        |  return renamed1: Int
+        |  return x_renamed_1: Int
         |}
         |""".stripMargin
     assertRenamedTo(input, expected)
@@ -73,9 +73,9 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |def renamed0() = {
-        |  var renamed1 @ global = (renamed0: (Int) => Int @ {})(4);
-        |  return renamed1: Int
+        |def foo_renamed_0() = {
+        |  var x_renamed_1 @ global = (foo_renamed_0: (Int) => Int @ {})(4);
+        |  return x_renamed_1: Int
         |}
         |""".stripMargin
     assertRenamedTo(input, expected)
@@ -85,15 +85,15 @@ class TestRenamerTests extends CoreTests {
     val input =
       """module main
         |
-        |def renamed0(renamed1: Int) = {
-        |  return renamed1: Int
+        |def f(x: Int) = {
+        |  return x: Int
         |}
         |""".stripMargin
     val expected =
       """module main
         |
-        |def renamed0(renamed1: Int) = {
-        |  return renamed1: Int
+        |def f_renamed_0(x_renamed_1: Int) = {
+        |  return x_renamed_1: Int
         |}
         |""".stripMargin
     assertRenamedTo(input, expected)
@@ -113,14 +113,14 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |type renamed1 {
-        |  renamed0(a: Int, b: Int)
+        |type Data_renamed_1 {
+        |  X_renamed_0(a: Int, b: Int)
         |}
         |
-        |def renamed2() = {
-        |  12 match [Int] {
-        |    X : { (renamed3: Int, renamed4: Int) =>
-        |      return renamed3: Int
+        |def foo_renamed_2() = {
+        |  12 match {
+        |    X : { (aa_renamed_3: Int, bb_renamed_4: Int) =>
+        |      return aa_renamed_3: Int
         |    }
         |  }
         |}
@@ -139,8 +139,8 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |def renamed0['renamed1](renamed2: Identity[renamed1]) = {
-        |  return renamed2: Identity[renamed1]
+        |def foo_renamed_0['A_renamed_1](a_renamed_2: A_renamed_1) = {
+        |  return a_renamed_2: Identity[A_renamed_1]
         |}
         |""".stripMargin
     assertRenamedTo(input, expected)
@@ -161,17 +161,17 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |def renamed0() = {
+        |def bar_renamed_0() = {
         |  return 1
         |}
-        |def renamed1() = {
-        |  def renamed2() = {
-        |    renamed0: () => Unit @ {}()
+        |def main_renamed_1() = {
+        |  def foo_renamed_2() = {
+        |    bar_renamed_0: () => Unit @ {}()
         |  }
-        |  def renamed3() = {
+        |  def bar_renamed_3() = {
         |    return 2
         |  }
-        |  renamed2: () => Unit @ {}()
+        |  foo_renamed_2: () => Unit @ {}()
         |}
         |""".stripMargin
 
@@ -191,10 +191,10 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |def renamed0() = {
-        |  let renamed1 = 1
-        |  let renamed2 = 2
-        |  return renamed2: Int
+        |def main_renamed_0() = {
+        |  let x_renamed_1 = 1
+        |  let x_renamed_2 = 2
+        |  return x_renamed_2: Int
         |}
         |""".stripMargin
 
diff --git a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
index c8e560af2e..7ce072ff02 100644
--- a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
+++ b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
@@ -14,6 +14,11 @@ object PrettyPrinter extends ParenPrettyPrinter {
 
   override val defaultIndent = 2
 
+  def formatHumanReadable(t: ModuleDecl): Document = {
+    val renamer = effekt.core.TestRenamer(Names(builtins.coreBuiltins))
+    format(renamer(t))
+  }
+
   def format(t: ModuleDecl): Document =
     pretty(toDoc(t), 4)
 
diff --git a/effekt/jvm/src/test/scala/effekt/core/TestRenamer.scala b/effekt/shared/src/main/scala/effekt/core/TestRenamer.scala
similarity index 95%
rename from effekt/jvm/src/test/scala/effekt/core/TestRenamer.scala
rename to effekt/shared/src/main/scala/effekt/core/TestRenamer.scala
index ca70ff1551..77b29e6ebe 100644
--- a/effekt/jvm/src/test/scala/effekt/core/TestRenamer.scala
+++ b/effekt/shared/src/main/scala/effekt/core/TestRenamer.scala
@@ -1,7 +1,7 @@
 package effekt.core
 
-import effekt.{Template, core, symbols}
 import effekt.symbols.builtins
+import effekt.{Template, core, symbols}
 
 /**
  * Freshens bound names in a given term for tests.
@@ -14,7 +14,7 @@ import effekt.symbols.builtins
  *
  * @param C the context is used to copy annotations from old symbols to fresh symbols
  */
-class TestRenamer(names: Names = Names(Map.empty), prefix: String = "_") extends core.Tree.Rewrite {
+class TestRenamer(names: Names = Names(Map.empty), prefix: String = "$") extends core.Tree.Rewrite {
 
   // list of scopes that map bound symbols to their renamed variants.
   private var scopes: List[Map[Id, Id]] = List.empty
@@ -31,6 +31,14 @@ class TestRenamer(names: Names = Names(Map.empty), prefix: String = "_") extends
     if (names.isKnown(id)) {
       return names.getKnown(id).get
     }
+    // To generate human-readable names, we include the user-provided string.
+    // To ensure idempotent printing, we strip any existing prefix from the name.
+    // This assumes that user-provided names to not include `prefix`.
+    val userName = if (id.name.name.contains(prefix)) {
+      id.name.name.substring(0, id.name.name.lastIndexOf(prefix))
+    } else {
+      id.name.name
+    }
     // HACK: This is an unfortunate hack.
     // TestRenamer is often used to check for alpha-equivalence by renaming both sides of a comparison.
     // However, Effekt requires globally unique Barendregt indices for all symbols, so just creating fresh
@@ -38,7 +46,7 @@ class TestRenamer(names: Names = Names(Map.empty), prefix: String = "_") extends
     // comparison get the same fresh Id for a given original Id.
     // This is achieved by generating a deterministic string `uniqueName` on both sides, and looking it up in `names`,
     // which generates a unique Id for it once and reuses it on subsequent lookups.
-    val uniqueName = prefix + suffix.toString
+    val uniqueName = userName + prefix + suffix.toString
     suffix = suffix + 1
     names.idFor(uniqueName)
 
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
index 991b6a5408..7ded90297d 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
@@ -36,7 +36,7 @@ trait ChezScheme extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez")
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter.format(res.core) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter.formatHumanReadable(res.core) }
     case Stage.CPS => None
     case Stage.Machine => None
     case Stage.Target => Separate(source).map { res => pretty(res) }
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
index f7506b52cb..d3c6ed494f 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
@@ -14,8 +14,8 @@ class ChezSchemeCPS extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez", "chezCPS")
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter.format(res) }
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter.format(res.core) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter.formatHumanReadable(res) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter.formatHumanReadable(res.core) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
     case Stage.Machine => None
     case Stage.Target => LSP(source)
diff --git a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
index b10848ac42..5024883b61 100644
--- a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
@@ -18,9 +18,9 @@ class JavaScript(additionalFeatureFlags: List[String] = Nil) extends Compiler[St
   override def supportedFeatureFlags: List[String] = additionalFeatureFlags ++ TransformerCps.jsFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter.format(res) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter.formatHumanReadable(res) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter.format(res.core) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter.formatHumanReadable(res.core) }
     case Stage.Machine => None
     case Stage.Target => CompileLSP(source).map { pretty }
   }
diff --git a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
index 11d05e0ea1..0973152ced 100644
--- a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
@@ -18,7 +18,7 @@ class LLVM extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = Transformer.llvmFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => steps.afterCore(source).map { res => core.PrettyPrinter.format(res.core) }
+    case Stage.Core => steps.afterCore(source).map { res => core.PrettyPrinter.formatHumanReadable(res.core) }
     case Stage.CPS => None
     case Stage.Machine => steps.afterMachine(source).map { res => machine.PrettyPrinter.format(res.program) }
     case Stage.Target => steps.afterLLVM(source).map { res => pretty(res) }

From 6f1e18ecff271b70ae93e1ab39c584a47340e797 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Mon, 1 Dec 2025 13:54:32 +0100
Subject: [PATCH 02/11] Elide some details when printing core for human
 inspection

---
 .../effekt/core/DeclarationContext.scala      |  2 +-
 .../scala/effekt/core/PrettyPrinter.scala     | 35 +++++++++++--------
 .../effekt/generator/chez/ChezScheme.scala    |  2 +-
 .../effekt/generator/chez/ChezSchemeCPS.scala |  4 +--
 .../effekt/generator/js/JavaScript.scala      |  4 +--
 .../scala/effekt/generator/llvm/LLVM.scala    |  2 +-
 .../src/main/scala/effekt/util/Debug.scala    |  2 +-
 7 files changed, 29 insertions(+), 22 deletions(-)

diff --git a/effekt/shared/src/main/scala/effekt/core/DeclarationContext.scala b/effekt/shared/src/main/scala/effekt/core/DeclarationContext.scala
index a4c53987c2..2627395377 100644
--- a/effekt/shared/src/main/scala/effekt/core/DeclarationContext.scala
+++ b/effekt/shared/src/main/scala/effekt/core/DeclarationContext.scala
@@ -1,7 +1,7 @@
 package effekt.core
 
 import effekt.util.messages.ErrorReporter
-import PrettyPrinter.*
+import HumanReadablePrettyPrinter.*
 
 /**
  * Context for transformations of a [[core.ModuleDecl]] that provides the declarations for this module.
diff --git a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
index 7ce072ff02..e84b97b982 100644
--- a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
+++ b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
@@ -4,21 +4,14 @@ package core
 import effekt.core.Type.{ PromptSymbol, ResumeSymbol, TChar }
 import effekt.source.FeatureFlag
 import kiama.output.ParenPrettyPrinter
+import kiama.output.PrettyPrinterTypes.Document
 
 import scala.language.implicitConversions
 import effekt.symbols.{ Name, Wildcard, builtins }
 
-object PrettyPrinter extends ParenPrettyPrinter {
-
-  import kiama.output.PrettyPrinterTypes.Document
-
+class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
   override val defaultIndent = 2
 
-  def formatHumanReadable(t: ModuleDecl): Document = {
-    val renamer = effekt.core.TestRenamer(Names(builtins.coreBuiltins))
-    format(renamer(t))
-  }
-
   def format(t: ModuleDecl): Document =
     pretty(toDoc(t), 4)
 
@@ -61,9 +54,9 @@ object PrettyPrinter extends ParenPrettyPrinter {
     // The order of toplevel items must match the parser (where the order is currently fixed).
     val includes = vsep(m.includes.map { im => "import" <+> im })
     val decls = vsep(m.declarations.map(toDoc))
-    val externs = vsep(m.externs.map(toDoc))
+    val externs = if humanReadable then emptyDoc else vsep(m.externs.map(toDoc))
     val defs = toDoc(m.definitions)
-    val exports = vsep(m.exports.map { id => "export" <+> toDoc(id) })
+    val exports = if humanReadable then emptyDoc else vsep(m.exports.map { id => "export" <+> toDoc(id) })
 
     "module" <+> m.path <>
       emptyline <>
@@ -106,7 +99,7 @@ object PrettyPrinter extends ParenPrettyPrinter {
 
   def toDoc(b: Block, preventBraces: Boolean = false): Doc = b match {
     case BlockVar(id, tpe, capt) =>
-      toDoc(id) <> ":" <+> toDoc(tpe) <+> "@" <+> toDoc(capt)
+      toDoc(id) <> (if humanReadable then emptyDoc else ":" <+> toDoc(tpe) <+> "@" <+> toDoc(capt))
     case BlockLit(tps, cps, vps, bps, body) =>
       val doc = space <> paramsToDoc(tps, cps, vps, bps) <+> "=>" <+> nest(line <> toDocStmts(body)) <> line
       if preventBraces then doc else braces { doc }
@@ -129,8 +122,7 @@ object PrettyPrinter extends ParenPrettyPrinter {
     case Literal(n, Type.TChar) => s"'\\${n.toString}'"
     case Literal(s: String, _)  => stringLiteral(s)
     case Literal(value, _)      => value.toString
-    case ValueVar(id, tpe)      => toDoc(id) <> ":" <+> toDoc(tpe)
-
+    case ValueVar(id, tpe)         => toDoc(id) <> (if humanReadable then emptyDoc else ":" <+> toDoc(tpe))
     case PureApp(b, targs, vargs)  => parens(toDoc(b)) <> argsToDoc(targs, vargs, Nil)
     case Make(data, tag, targs, vargs)    => "make" <+> toDoc(data) <+> toDoc(tag) <> argsToDoc(targs, vargs, Nil)
 
@@ -351,3 +343,18 @@ object PrettyPrinter extends ParenPrettyPrinter {
     multi <> s <> multi
   }
 }
+
+/**
+ * Instance of PrettyPrinter that produces output that can be parsed back by the core parser.
+ */
+object ReparsablePrettyPrinter extends PrettyPrinter(false) {}
+
+/**
+ * Instance of PrettyPrinter that produces less verbose, more human-readable output.
+ */
+object HumanReadablePrettyPrinter extends PrettyPrinter(true) {
+  def renameAndFormat(t: ModuleDecl): Document = {
+    val renamer = effekt.core.TestRenamer(Names(builtins.coreBuiltins))
+    format(renamer(t))
+  }
+}
\ No newline at end of file
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
index 7ded90297d..83b929a7bd 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
@@ -36,7 +36,7 @@ trait ChezScheme extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez")
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter.formatHumanReadable(res.core) }
+    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.renameAndFormat(res.core) }
     case Stage.CPS => None
     case Stage.Machine => None
     case Stage.Target => Separate(source).map { res => pretty(res) }
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
index d3c6ed494f..bac68bb59f 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
@@ -14,8 +14,8 @@ class ChezSchemeCPS extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez", "chezCPS")
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter.formatHumanReadable(res) }
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter.formatHumanReadable(res.core) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.HumanReadablePrettyPrinter.renameAndFormat(res) }
+    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.renameAndFormat(res.core) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
     case Stage.Machine => None
     case Stage.Target => LSP(source)
diff --git a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
index 5024883b61..2f7a7d6ea9 100644
--- a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
@@ -18,9 +18,9 @@ class JavaScript(additionalFeatureFlags: List[String] = Nil) extends Compiler[St
   override def supportedFeatureFlags: List[String] = additionalFeatureFlags ++ TransformerCps.jsFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter.formatHumanReadable(res) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.HumanReadablePrettyPrinter.renameAndFormat(res) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter.formatHumanReadable(res.core) }
+    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.renameAndFormat(res.core) }
     case Stage.Machine => None
     case Stage.Target => CompileLSP(source).map { pretty }
   }
diff --git a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
index 0973152ced..d01393f56b 100644
--- a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
@@ -18,7 +18,7 @@ class LLVM extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = Transformer.llvmFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => steps.afterCore(source).map { res => core.PrettyPrinter.formatHumanReadable(res.core) }
+    case Stage.Core => steps.afterCore(source).map { res => core.HumanReadablePrettyPrinter.renameAndFormat(res.core) }
     case Stage.CPS => None
     case Stage.Machine => steps.afterMachine(source).map { res => machine.PrettyPrinter.format(res.program) }
     case Stage.Target => steps.afterLLVM(source).map { res => pretty(res) }
diff --git a/effekt/shared/src/main/scala/effekt/util/Debug.scala b/effekt/shared/src/main/scala/effekt/util/Debug.scala
index 8efbe62edd..0e71f9a3d4 100644
--- a/effekt/shared/src/main/scala/effekt/util/Debug.scala
+++ b/effekt/shared/src/main/scala/effekt/util/Debug.scala
@@ -14,7 +14,7 @@ val showGeneric: PartialFunction[Any, String] = {
 
 val show: PartialFunction[Any, String] =
   TypePrinter.show orElse
-    core.PrettyPrinter.show orElse
+    core.HumanReadablePrettyPrinter.show orElse
     generator.js.PrettyPrinter.show orElse
     cps.PrettyPrinter.show orElse
     machine.PrettyPrinter.show orElse

From 88d2650b65d8fc199c47e6ed97e3c5093e5aa09d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Mon, 1 Dec 2025 13:59:05 +0100
Subject: [PATCH 03/11] Fix remaining uses of PrettyPrinter.format

---
 .../jvm/src/test/scala/effekt/core/CoreTests.scala   | 12 ++++++------
 .../src/test/scala/effekt/core/ReparseTests.scala    |  4 ++--
 .../test/scala/effekt/core/TestRenamerTests.scala    |  4 ++--
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/effekt/jvm/src/test/scala/effekt/core/CoreTests.scala b/effekt/jvm/src/test/scala/effekt/core/CoreTests.scala
index 144223bcd0..d79a82517c 100644
--- a/effekt/jvm/src/test/scala/effekt/core/CoreTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/core/CoreTests.scala
@@ -19,11 +19,11 @@ trait CoreTests extends munit.FunSuite {
         |=====================
         |Got:
         |----
-        |${effekt.core.PrettyPrinter.format(obtained).layout}
+        |${effekt.core.ReparsablePrettyPrinter.format(obtained).layout}
         |
         |Expected:
         |---------
-        |${effekt.core.PrettyPrinter.format(expected).layout}
+        |${effekt.core.ReparsablePrettyPrinter.format(expected).layout}
         |
         |""".stripMargin
     })
@@ -34,11 +34,11 @@ trait CoreTests extends munit.FunSuite {
         |=====================
         |Got:
         |----
-        |${effekt.core.PrettyPrinter.format(obtained)}
+        |${effekt.core.ReparsablePrettyPrinter.format(obtained)}
         |
         |Expected:
         |---------
-        |${effekt.core.PrettyPrinter.format(expected)}
+        |${effekt.core.ReparsablePrettyPrinter.format(expected)}
         |
         |""".stripMargin
     })
@@ -50,8 +50,8 @@ trait CoreTests extends munit.FunSuite {
     val renamer = TestRenamer(names)
     val obtainedRenamed = renamer(obtained)
     val expectedRenamed = renamer(expected)
-    val obtainedPrinted = effekt.core.PrettyPrinter.format(obtainedRenamed).layout
-    val expectedPrinted = effekt.core.PrettyPrinter.format(expectedRenamed).layout
+    val obtainedPrinted = effekt.core.ReparsablePrettyPrinter.format(obtainedRenamed).layout
+    val expectedPrinted = effekt.core.ReparsablePrettyPrinter.format(expectedRenamed).layout
     assertEquals(obtainedPrinted, expectedPrinted)
     shouldBeEqual(obtainedRenamed, expectedRenamed, clue)
   }
diff --git a/effekt/jvm/src/test/scala/effekt/core/ReparseTests.scala b/effekt/jvm/src/test/scala/effekt/core/ReparseTests.scala
index 44edb7972e..4c00ba20d9 100644
--- a/effekt/jvm/src/test/scala/effekt/core/ReparseTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/core/ReparseTests.scala
@@ -75,7 +75,7 @@ class ReparseTests extends CoreTests {
     }
     val renamer = TestRenamer(Names(defaultNames))
     val expectedRenamed = renamer(coreMod)
-    val printed = core.PrettyPrinter.format(expectedRenamed).layout
+    val printed = core.ReparsablePrettyPrinter.format(expectedRenamed).layout
     val reparsed: ModuleDecl = try { parse(printed)(using Location.empty) } catch {
       case e @ TypeError(msg, context) =>
          println(e.toString)
@@ -86,7 +86,7 @@ class ReparseTests extends CoreTests {
         throw e
     }
     val reparsedRenamed = renamer(reparsed)
-    val reparsedPrinted = core.PrettyPrinter.format(reparsedRenamed).layout
+    val reparsedPrinted = core.ReparsablePrettyPrinter.format(reparsedRenamed).layout
     val expectedPrinted = printed
     assertEquals(reparsedPrinted, expectedPrinted)
   }
diff --git a/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala b/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
index 8df6d4c907..9b0357c7f5 100644
--- a/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
@@ -14,8 +14,8 @@ class TestRenamerTests extends CoreTests {
     val pExpected = parse(renamed, "expected", names)
     val renamer = new TestRenamer(names, "_renamed_") // use "renamed" as prefix so we can refer to it
     val obtained = renamer(pInput)
-    val obtainedPrinted = effekt.core.PrettyPrinter.format(obtained).layout
-    val expectedPrinted = effekt.core.PrettyPrinter.format(pExpected).layout
+    val obtainedPrinted = effekt.core.ReparsablePrettyPrinter.format(obtained).layout
+    val expectedPrinted = effekt.core.ReparsablePrettyPrinter.format(pExpected).layout
     assertEquals(obtainedPrinted, expectedPrinted)
     shouldBeEqual(obtained, pExpected, clue)
   }

From 889b4d186b4c51d47643286c5fcc489762529b9e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Mon, 1 Dec 2025 14:08:40 +0100
Subject: [PATCH 04/11] Do not include user-annotated name when checking for
 alpha conversion

---
 effekt/jvm/src/test/scala/effekt/core/CoreTests.scala     | 4 ++--
 .../shared/src/main/scala/effekt/core/TestRenamer.scala   | 8 ++++++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/effekt/jvm/src/test/scala/effekt/core/CoreTests.scala b/effekt/jvm/src/test/scala/effekt/core/CoreTests.scala
index d79a82517c..3525a22fed 100644
--- a/effekt/jvm/src/test/scala/effekt/core/CoreTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/core/CoreTests.scala
@@ -47,7 +47,7 @@ trait CoreTests extends munit.FunSuite {
                             expected: ModuleDecl,
                             clue: => Any = "values are not alpha-equivalent",
                             names: Names = Names(defaultNames))(using Location): Unit = {
-    val renamer = TestRenamer(names)
+    val renamer = TestRenamer(names, preserveUserAnnotatedPrefix=false)
     val obtainedRenamed = renamer(obtained)
     val expectedRenamed = renamer(expected)
     val obtainedPrinted = effekt.core.ReparsablePrettyPrinter.format(obtainedRenamed).layout
@@ -59,7 +59,7 @@ trait CoreTests extends munit.FunSuite {
                             expected: Stmt,
                             clue: => Any = "values are not alpha-equivalent",
                             names: Names = Names(defaultNames))(using Location): Unit = {
-    val renamer = TestRenamer(names)
+    val renamer = TestRenamer(names, preserveUserAnnotatedPrefix=false)
     shouldBeEqual(renamer(obtained), renamer(expected), clue)
   }
   def parse(input: String,
diff --git a/effekt/shared/src/main/scala/effekt/core/TestRenamer.scala b/effekt/shared/src/main/scala/effekt/core/TestRenamer.scala
index 77b29e6ebe..a7893a7cff 100644
--- a/effekt/shared/src/main/scala/effekt/core/TestRenamer.scala
+++ b/effekt/shared/src/main/scala/effekt/core/TestRenamer.scala
@@ -14,7 +14,7 @@ import effekt.{Template, core, symbols}
  *
  * @param C the context is used to copy annotations from old symbols to fresh symbols
  */
-class TestRenamer(names: Names = Names(Map.empty), prefix: String = "$") extends core.Tree.Rewrite {
+class TestRenamer(names: Names = Names(Map.empty), prefix: String = "$", preserveUserAnnotatedPrefix: Boolean = true) extends core.Tree.Rewrite {
 
   // list of scopes that map bound symbols to their renamed variants.
   private var scopes: List[Map[Id, Id]] = List.empty
@@ -39,6 +39,10 @@ class TestRenamer(names: Names = Names(Map.empty), prefix: String = "$") extends
     } else {
       id.name.name
     }
+    // For many purposes, we would like to include the user-annotated name in the fresh id,
+    // so that printed terms are more readable.
+    // However, we do not want to include it when checking for alpha-equivalence in tests.
+    val userPart = if preserveUserAnnotatedPrefix then userName else ""
     // HACK: This is an unfortunate hack.
     // TestRenamer is often used to check for alpha-equivalence by renaming both sides of a comparison.
     // However, Effekt requires globally unique Barendregt indices for all symbols, so just creating fresh
@@ -46,7 +50,7 @@ class TestRenamer(names: Names = Names(Map.empty), prefix: String = "$") extends
     // comparison get the same fresh Id for a given original Id.
     // This is achieved by generating a deterministic string `uniqueName` on both sides, and looking it up in `names`,
     // which generates a unique Id for it once and reuses it on subsequent lookups.
-    val uniqueName = userName + prefix + suffix.toString
+    val uniqueName = userPart + prefix + suffix.toString
     suffix = suffix + 1
     names.idFor(uniqueName)
 

From a8996d8a4238de5d10d6fc2f9a28e57efa134f8b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Wed, 3 Dec 2025 09:58:42 +0100
Subject: [PATCH 05/11] Print full Barendregt id

---
 .../src/main/scala/effekt/core/PrettyPrinter.scala     | 10 ++++++++--
 .../main/scala/effekt/generator/chez/ChezScheme.scala  |  2 +-
 .../scala/effekt/generator/chez/ChezSchemeCPS.scala    |  4 ++--
 .../main/scala/effekt/generator/js/JavaScript.scala    |  4 ++--
 .../src/main/scala/effekt/generator/llvm/LLVM.scala    |  2 +-
 5 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
index e84b97b982..c9fb1efea1 100644
--- a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
+++ b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
@@ -113,8 +113,14 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
 
   //def toDoc(n: Name): Doc = n.toString
 
-  def toDoc(s: symbols.Symbol): Doc =
-    builtins.coreBuiltinSymbolToString(s).getOrElse(s.name.name)
+  def toDoc(s: symbols.Symbol): Doc = {
+    // In human-readable mode, we show the name together with the actual Barendregt id.
+    // This allows the user to connect the symbol to the internal representation when debugging.
+    // In reparsable mode, we just show the string part, which should be freshened by the TestRenamer before printing.
+    // The TestRenamer does not rename the Barendregt id because that would violate the internal invariant of having
+    // just a single global Barendregt namespace.
+    builtins.coreBuiltinSymbolToString(s).getOrElse(if humanReadable then s.show else s.name.name)
+  }
 
   def toDoc(e: Expr): Doc = e match {
     case Literal((), _)         => "()"
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
index 83b929a7bd..473d6ffdc8 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
@@ -36,7 +36,7 @@ trait ChezScheme extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez")
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.renameAndFormat(res.core) }
+    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.format(res.core) }
     case Stage.CPS => None
     case Stage.Machine => None
     case Stage.Target => Separate(source).map { res => pretty(res) }
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
index bac68bb59f..8fe0379fa4 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
@@ -14,8 +14,8 @@ class ChezSchemeCPS extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez", "chezCPS")
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.HumanReadablePrettyPrinter.renameAndFormat(res) }
-    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.renameAndFormat(res.core) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.HumanReadablePrettyPrinter.format(res) }
+    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.format(res.core) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
     case Stage.Machine => None
     case Stage.Target => LSP(source)
diff --git a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
index 2f7a7d6ea9..dac4bcd83d 100644
--- a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
@@ -18,9 +18,9 @@ class JavaScript(additionalFeatureFlags: List[String] = Nil) extends Compiler[St
   override def supportedFeatureFlags: List[String] = additionalFeatureFlags ++ TransformerCps.jsFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.HumanReadablePrettyPrinter.renameAndFormat(res) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.HumanReadablePrettyPrinter.format(res) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
-    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.renameAndFormat(res.core) }
+    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.format(res.core) }
     case Stage.Machine => None
     case Stage.Target => CompileLSP(source).map { pretty }
   }
diff --git a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
index d01393f56b..c373916f76 100644
--- a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
@@ -18,7 +18,7 @@ class LLVM extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = Transformer.llvmFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => steps.afterCore(source).map { res => core.HumanReadablePrettyPrinter.renameAndFormat(res.core) }
+    case Stage.Core => steps.afterCore(source).map { res => core.HumanReadablePrettyPrinter.format(res.core) }
     case Stage.CPS => None
     case Stage.Machine => steps.afterMachine(source).map { res => machine.PrettyPrinter.format(res.program) }
     case Stage.Target => steps.afterLLVM(source).map { res => pretty(res) }

From f83842292510270244e9cbb549f9a4107c540ece Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Wed, 3 Dec 2025 10:15:38 +0100
Subject: [PATCH 06/11] Hide more annotations in human-readable mode

---
 .../scala/effekt/core/PrettyPrinter.scala     | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
index c9fb1efea1..f16afc78d3 100644
--- a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
+++ b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
@@ -129,9 +129,12 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
     case Literal(s: String, _)  => stringLiteral(s)
     case Literal(value, _)      => value.toString
     case ValueVar(id, tpe)         => toDoc(id) <> (if humanReadable then emptyDoc else ":" <+> toDoc(tpe))
-    case PureApp(b, targs, vargs)  => parens(toDoc(b)) <> argsToDoc(targs, vargs, Nil)
-    case Make(data, tag, targs, vargs)    => "make" <+> toDoc(data) <+> toDoc(tag) <> argsToDoc(targs, vargs, Nil)
-
+    case PureApp(b, targs, vargs)  => (if humanReadable then toDoc(b) else parens(toDoc(b))) <> argsToDoc(targs, vargs, Nil)
+    case Make(data, tag, targs, vargs)    =>
+      if humanReadable then
+        "make" <+> toDoc(tag) <> argsToDoc(targs, vargs, Nil)
+      else
+        "make" <+> toDoc(data) <+> toDoc(tag) <> argsToDoc(targs, vargs, Nil)
     case Box(b, capt) => "box" <+> toDoc(capt) <+> toDoc(b)
   }
 
@@ -238,7 +241,8 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
       toDoc(b) <> argsToDoc(targs, vargs, bargs)
 
     case Invoke(b, method, methodTpe, targs, vargs, bargs) =>
-      toDoc(b) <> "." <> toDoc(method) <> ":" <+> toDoc(methodTpe) <> argsToDoc(targs, vargs, bargs)
+      val pTpe = if humanReadable then emptyDoc else ":" <+> toDoc(methodTpe)
+      toDoc(b) <> "." <> toDoc(method) <> pTpe <> argsToDoc(targs, vargs, bargs)
 
     case If(cond, thn, els) =>
       "if" <+> parens(toDoc(cond)) <+> block(toDocStmts(thn)) <+> "else" <+> block(toDocStmts(els))
@@ -358,9 +362,4 @@ object ReparsablePrettyPrinter extends PrettyPrinter(false) {}
 /**
  * Instance of PrettyPrinter that produces less verbose, more human-readable output.
  */
-object HumanReadablePrettyPrinter extends PrettyPrinter(true) {
-  def renameAndFormat(t: ModuleDecl): Document = {
-    val renamer = effekt.core.TestRenamer(Names(builtins.coreBuiltins))
-    format(renamer(t))
-  }
-}
\ No newline at end of file
+object HumanReadablePrettyPrinter extends PrettyPrinter(true) {}

From e75099935817b70fddc99c1bbeea8dce41873301 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Wed, 3 Dec 2025 11:18:52 +0100
Subject: [PATCH 07/11] Add --detailed-ir flag

---
 .../src/main/scala/effekt/EffektConfig.scala  |  2 ++
 .../src/main/scala/effekt/EffektConfig.scala  | 11 ++++++++
 .../scala/effekt/core/PrettyPrinter.scala     | 28 ++++++++++---------
 .../effekt/generator/chez/ChezScheme.scala    |  2 +-
 .../effekt/generator/chez/ChezSchemeCPS.scala |  4 +--
 .../effekt/generator/js/JavaScript.scala      |  4 +--
 .../scala/effekt/generator/llvm/LLVM.scala    |  2 +-
 7 files changed, 34 insertions(+), 19 deletions(-)

diff --git a/effekt/js/src/main/scala/effekt/EffektConfig.scala b/effekt/js/src/main/scala/effekt/EffektConfig.scala
index 8b50b1eabf..44b6e88daf 100644
--- a/effekt/js/src/main/scala/effekt/EffektConfig.scala
+++ b/effekt/js/src/main/scala/effekt/EffektConfig.scala
@@ -39,4 +39,6 @@ trait EffektConfig {
   def timed() = false
 
   def debug() = false
+
+  def printDetailedIR(): Boolean = false
 }
diff --git a/effekt/jvm/src/main/scala/effekt/EffektConfig.scala b/effekt/jvm/src/main/scala/effekt/EffektConfig.scala
index 154b499749..0760892e32 100644
--- a/effekt/jvm/src/main/scala/effekt/EffektConfig.scala
+++ b/effekt/jvm/src/main/scala/effekt/EffektConfig.scala
@@ -164,6 +164,15 @@ class EffektConfig(args: Seq[String]) extends REPLConfig(args.takeWhile(_ != "--
     group = debugging
   )
 
+  val detailedIR: ScallopOption[Boolean] = toggle(
+    "detailed-ir",
+    descrYes = "Print detailed IR with all annotations",
+    default = Some(false),
+    noshort = true,
+    prefix = "no-",
+    group = debugging
+  )
+
   val showDocumentation: ScallopOption[Boolean] = toggle(
     "show-documentation",
     descrYes = "Show all documented statements as a JSON",
@@ -263,6 +272,8 @@ class EffektConfig(args: Seq[String]) extends REPLConfig(args.takeWhile(_ != "--
 
   def timed(): Boolean = time.isSupplied && !server()
 
+  def printDetailedIR(): Boolean = detailedIR()
+
   validateFilesIsDirectory(includePath)
 
   // force some other configs manually to initialize them when compiling with native-image
diff --git a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
index f16afc78d3..803d44be3d 100644
--- a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
+++ b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
@@ -9,7 +9,7 @@ import kiama.output.PrettyPrinterTypes.Document
 import scala.language.implicitConversions
 import effekt.symbols.{ Name, Wildcard, builtins }
 
-class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
+class PrettyPrinter(printDetails: Boolean) extends ParenPrettyPrinter {
   override val defaultIndent = 2
 
   def format(t: ModuleDecl): Document =
@@ -54,9 +54,9 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
     // The order of toplevel items must match the parser (where the order is currently fixed).
     val includes = vsep(m.includes.map { im => "import" <+> im })
     val decls = vsep(m.declarations.map(toDoc))
-    val externs = if humanReadable then emptyDoc else vsep(m.externs.map(toDoc))
+    val externs = if printDetails then vsep(m.externs.map(toDoc)) else emptyDoc
     val defs = toDoc(m.definitions)
-    val exports = if humanReadable then emptyDoc else vsep(m.exports.map { id => "export" <+> toDoc(id) })
+    val exports = if printDetails then vsep(m.exports.map { id => "export" <+> toDoc(id) }) else emptyDoc
 
     "module" <+> m.path <>
       emptyline <>
@@ -99,7 +99,7 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
 
   def toDoc(b: Block, preventBraces: Boolean = false): Doc = b match {
     case BlockVar(id, tpe, capt) =>
-      toDoc(id) <> (if humanReadable then emptyDoc else ":" <+> toDoc(tpe) <+> "@" <+> toDoc(capt))
+      toDoc(id) <> (if printDetails then ":" <+> toDoc(tpe) <+> "@" <+> toDoc(capt) else emptyDoc)
     case BlockLit(tps, cps, vps, bps, body) =>
       val doc = space <> paramsToDoc(tps, cps, vps, bps) <+> "=>" <+> nest(line <> toDocStmts(body)) <> line
       if preventBraces then doc else braces { doc }
@@ -119,7 +119,7 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
     // In reparsable mode, we just show the string part, which should be freshened by the TestRenamer before printing.
     // The TestRenamer does not rename the Barendregt id because that would violate the internal invariant of having
     // just a single global Barendregt namespace.
-    builtins.coreBuiltinSymbolToString(s).getOrElse(if humanReadable then s.show else s.name.name)
+    builtins.coreBuiltinSymbolToString(s).getOrElse(if printDetails then s.name.name else s.show)
   }
 
   def toDoc(e: Expr): Doc = e match {
@@ -128,13 +128,13 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
     case Literal(n, Type.TChar) => s"'\\${n.toString}'"
     case Literal(s: String, _)  => stringLiteral(s)
     case Literal(value, _)      => value.toString
-    case ValueVar(id, tpe)         => toDoc(id) <> (if humanReadable then emptyDoc else ":" <+> toDoc(tpe))
-    case PureApp(b, targs, vargs)  => (if humanReadable then toDoc(b) else parens(toDoc(b))) <> argsToDoc(targs, vargs, Nil)
+    case ValueVar(id, tpe)         => toDoc(id) <> (if printDetails then ":" <+> toDoc(tpe) else emptyDoc)
+    case PureApp(b, targs, vargs)  => (if printDetails then parens(toDoc(b)) else toDoc(b)) <> argsToDoc(targs, vargs, Nil)
     case Make(data, tag, targs, vargs)    =>
-      if humanReadable then
-        "make" <+> toDoc(tag) <> argsToDoc(targs, vargs, Nil)
-      else
+      if printDetails then
         "make" <+> toDoc(data) <+> toDoc(tag) <> argsToDoc(targs, vargs, Nil)
+      else
+        "make" <+> toDoc(tag) <> argsToDoc(targs, vargs, Nil)
     case Box(b, capt) => "box" <+> toDoc(capt) <+> toDoc(b)
   }
 
@@ -241,7 +241,7 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
       toDoc(b) <> argsToDoc(targs, vargs, bargs)
 
     case Invoke(b, method, methodTpe, targs, vargs, bargs) =>
-      val pTpe = if humanReadable then emptyDoc else ":" <+> toDoc(methodTpe)
+      val pTpe = if printDetails then ":" <+> toDoc(methodTpe) else emptyDoc
       toDoc(b) <> "." <> toDoc(method) <> pTpe <> argsToDoc(targs, vargs, bargs)
 
     case If(cond, thn, els) =>
@@ -356,10 +356,12 @@ class PrettyPrinter(humanReadable: Boolean) extends ParenPrettyPrinter {
 
 /**
  * Instance of PrettyPrinter that produces output that can be parsed back by the core parser.
+ * This corresponds to the `--detailed-ir` command line flag.
  */
-object ReparsablePrettyPrinter extends PrettyPrinter(false) {}
+object ReparsablePrettyPrinter extends PrettyPrinter(true) {}
 
 /**
  * Instance of PrettyPrinter that produces less verbose, more human-readable output.
+ * This is the default behavior for the `--ir-write-all` and `--ir-show` command line flags.
  */
-object HumanReadablePrettyPrinter extends PrettyPrinter(true) {}
+object HumanReadablePrettyPrinter extends PrettyPrinter(false) {}
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
index 473d6ffdc8..ca97dd519d 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
@@ -36,7 +36,7 @@ trait ChezScheme extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez")
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.format(res.core) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.printDetailedIR()).format(res.core) }
     case Stage.CPS => None
     case Stage.Machine => None
     case Stage.Target => Separate(source).map { res => pretty(res) }
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
index 8fe0379fa4..33d1d0351f 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
@@ -14,8 +14,8 @@ class ChezSchemeCPS extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez", "chezCPS")
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.HumanReadablePrettyPrinter.format(res) }
-    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.format(res.core) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter(Context.config.printDetailedIR()).format(res) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.printDetailedIR()).format(res.core) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
     case Stage.Machine => None
     case Stage.Target => LSP(source)
diff --git a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
index dac4bcd83d..d4990cef0a 100644
--- a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
@@ -18,9 +18,9 @@ class JavaScript(additionalFeatureFlags: List[String] = Nil) extends Compiler[St
   override def supportedFeatureFlags: List[String] = additionalFeatureFlags ++ TransformerCps.jsFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.HumanReadablePrettyPrinter.format(res) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter(Context.config.printDetailedIR()).format(res) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
-    case Stage.Core => Core(source).map { res => core.HumanReadablePrettyPrinter.format(res.core) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.printDetailedIR()).format(res.core) }
     case Stage.Machine => None
     case Stage.Target => CompileLSP(source).map { pretty }
   }
diff --git a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
index c373916f76..55fa9024ed 100644
--- a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
@@ -18,7 +18,7 @@ class LLVM extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = Transformer.llvmFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => steps.afterCore(source).map { res => core.HumanReadablePrettyPrinter.format(res.core) }
+    case Stage.Core => steps.afterCore(source).map { res => core.PrettyPrinter(Context.config.printDetailedIR()).format(res.core) }
     case Stage.CPS => None
     case Stage.Machine => steps.afterMachine(source).map { res => machine.PrettyPrinter.format(res.program) }
     case Stage.Target => steps.afterLLVM(source).map { res => pretty(res) }

From ee9c7ce501790742f0f8a879ec35d2685594014d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Wed, 10 Dec 2025 13:57:27 +0100
Subject: [PATCH 08/11] Hide more details when printing core by default

---
 .../scala/effekt/core/PrettyPrinter.scala     | 28 ++++++++++++++-----
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
index 803d44be3d..cfd2b8f287 100644
--- a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
+++ b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
@@ -109,7 +109,12 @@ class PrettyPrinter(printDetails: Boolean) extends ParenPrettyPrinter {
 
   def toDoc(p: ValueParam): Doc = toDoc(p.id) <> ":" <+> toDoc(p.tpe)
   def toDoc(p: BlockParam): Doc = braces(toDoc(p.id) <> ":" <+> toDoc(p.tpe))
-  def toDoc(cparam: Id, bparam: BlockParam): Doc = braces(toDoc(bparam.id) <+> "@" <+> toDoc(cparam) <> ":" <+> toDoc(bparam.tpe))
+  def toDoc(cparam: Id, bparam: BlockParam): Doc = {
+    if printDetails then
+      braces(toDoc(bparam.id) <+> "@" <+> toDoc(cparam) <> ":" <+> toDoc(bparam.tpe))
+    else
+      braces(toDoc(bparam.id) <> ":" <+> toDoc(bparam.tpe))
+  }
 
   //def toDoc(n: Name): Doc = n.toString
 
@@ -261,16 +266,25 @@ class PrettyPrinter(printDetails: Boolean) extends ParenPrettyPrinter {
         toDocStmts(body)
 
     case Var(ref, init, cap, body) =>
-      "var" <+> toDoc(ref) <+> "@" <+> toDoc(cap) <+> "=" <+> toDoc(init) <> ";" <> line <>
-        toDocStmts(body)
+      if printDetails then
+        "var" <+> toDoc(ref) <+> "@" <+> toDoc(cap) <+> "=" <+> toDoc(init) <> ";" <> line <> toDocStmts(body)
+      else
+        "var" <+> toDoc(ref) <+> "=" <+> toDoc(init) <> ";" <> line <> toDocStmts(body)
 
     case Get(id, tpe, ref, capt, body) =>
-      "get" <+> toDoc(id) <+> ":" <+> toDoc(tpe) <+> "=" <+> "!" <+> toDoc(ref) <+> "@" <+> toDocSingleCapture(capt) <> ";" <> line <>
-        toDocStmts(body)
+      if printDetails then
+        "get" <+> toDoc(id) <+> ":" <+> toDoc(tpe) <+> "=" <+> "!" <+> toDoc(ref) <+> "@" <+> toDocSingleCapture(capt) <> ";" <> line <>
+          toDocStmts(body)
+      else
+        "get" <+> toDoc(id) <+> "=" <+> "!" <+> toDoc(ref) <> ";" <> line <> toDocStmts(body)
 
     case Put(ref, capt, value, body) =>
-      "put" <+> toDoc(ref) <+> "@" <+> toDocSingleCapture(capt) <+> "=" <+> toDoc(value) <> ";" <> line <>
-        toDocStmts(body)
+      if printDetails then
+        "put" <+> toDoc(ref) <+> "@" <+> toDocSingleCapture(capt) <+> "=" <+> toDoc(value) <> ";" <> line <>
+          toDocStmts(body)
+      else
+        "put" <+> toDoc(ref) <+> "=" <+> toDoc(value) <> ";" <> line <>
+          toDocStmts(body)
 
     case Region(body) =>
       "region" <+> toDoc(body)

From 6250f8ab98b031e9a3a427719759a4189ad7ac7e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Wed, 10 Dec 2025 14:01:06 +0100
Subject: [PATCH 09/11] Replace --detailed-ir by --debug flag

---
 effekt/js/src/main/scala/effekt/EffektConfig.scala    |  2 --
 effekt/jvm/src/main/scala/effekt/EffektConfig.scala   | 11 -----------
 .../src/main/scala/effekt/core/PrettyPrinter.scala    |  2 +-
 .../main/scala/effekt/generator/chez/ChezScheme.scala |  2 +-
 .../scala/effekt/generator/chez/ChezSchemeCPS.scala   |  4 ++--
 .../main/scala/effekt/generator/js/JavaScript.scala   |  4 ++--
 .../src/main/scala/effekt/generator/llvm/LLVM.scala   |  2 +-
 7 files changed, 7 insertions(+), 20 deletions(-)

diff --git a/effekt/js/src/main/scala/effekt/EffektConfig.scala b/effekt/js/src/main/scala/effekt/EffektConfig.scala
index 44b6e88daf..8b50b1eabf 100644
--- a/effekt/js/src/main/scala/effekt/EffektConfig.scala
+++ b/effekt/js/src/main/scala/effekt/EffektConfig.scala
@@ -39,6 +39,4 @@ trait EffektConfig {
   def timed() = false
 
   def debug() = false
-
-  def printDetailedIR(): Boolean = false
 }
diff --git a/effekt/jvm/src/main/scala/effekt/EffektConfig.scala b/effekt/jvm/src/main/scala/effekt/EffektConfig.scala
index 0760892e32..154b499749 100644
--- a/effekt/jvm/src/main/scala/effekt/EffektConfig.scala
+++ b/effekt/jvm/src/main/scala/effekt/EffektConfig.scala
@@ -164,15 +164,6 @@ class EffektConfig(args: Seq[String]) extends REPLConfig(args.takeWhile(_ != "--
     group = debugging
   )
 
-  val detailedIR: ScallopOption[Boolean] = toggle(
-    "detailed-ir",
-    descrYes = "Print detailed IR with all annotations",
-    default = Some(false),
-    noshort = true,
-    prefix = "no-",
-    group = debugging
-  )
-
   val showDocumentation: ScallopOption[Boolean] = toggle(
     "show-documentation",
     descrYes = "Show all documented statements as a JSON",
@@ -272,8 +263,6 @@ class EffektConfig(args: Seq[String]) extends REPLConfig(args.takeWhile(_ != "--
 
   def timed(): Boolean = time.isSupplied && !server()
 
-  def printDetailedIR(): Boolean = detailedIR()
-
   validateFilesIsDirectory(includePath)
 
   // force some other configs manually to initialize them when compiling with native-image
diff --git a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
index cfd2b8f287..b740574c14 100644
--- a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
+++ b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
@@ -370,7 +370,7 @@ class PrettyPrinter(printDetails: Boolean) extends ParenPrettyPrinter {
 
 /**
  * Instance of PrettyPrinter that produces output that can be parsed back by the core parser.
- * This corresponds to the `--detailed-ir` command line flag.
+ * This can be enabled using the `--debug` command line flag.
  */
 object ReparsablePrettyPrinter extends PrettyPrinter(true) {}
 
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
index ca97dd519d..08700a6eb7 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezScheme.scala
@@ -36,7 +36,7 @@ trait ChezScheme extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez")
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.printDetailedIR()).format(res.core) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.debug()).format(res.core) }
     case Stage.CPS => None
     case Stage.Machine => None
     case Stage.Target => Separate(source).map { res => pretty(res) }
diff --git a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
index 33d1d0351f..1260bc4625 100644
--- a/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/chez/ChezSchemeCPS.scala
@@ -14,8 +14,8 @@ class ChezSchemeCPS extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = List("chez", "chezCPS")
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter(Context.config.printDetailedIR()).format(res) }
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.printDetailedIR()).format(res.core) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter(Context.config.debug()).format(res) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.debug()).format(res.core) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
     case Stage.Machine => None
     case Stage.Target => LSP(source)
diff --git a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
index d4990cef0a..1c860b065d 100644
--- a/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/js/JavaScript.scala
@@ -18,9 +18,9 @@ class JavaScript(additionalFeatureFlags: List[String] = Nil) extends Compiler[St
   override def supportedFeatureFlags: List[String] = additionalFeatureFlags ++ TransformerCps.jsFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using C: Context): Option[Document] = stage match {
-    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter(Context.config.printDetailedIR()).format(res) }
+    case Stage.Core if C.config.optimize() => Optimized(source).map { (_, _, res) => core.PrettyPrinter(Context.config.debug()).format(res) }
     case Stage.CPS => CPSTransformed(source).map { (_, _, _, res) => cps.PrettyPrinter.format(res) }
-    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.printDetailedIR()).format(res.core) }
+    case Stage.Core => Core(source).map { res => core.PrettyPrinter(Context.config.debug()).format(res.core) }
     case Stage.Machine => None
     case Stage.Target => CompileLSP(source).map { pretty }
   }
diff --git a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
index 55fa9024ed..79c58984ba 100644
--- a/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
+++ b/effekt/shared/src/main/scala/effekt/generator/llvm/LLVM.scala
@@ -18,7 +18,7 @@ class LLVM extends Compiler[String] {
   override def supportedFeatureFlags: List[String] = Transformer.llvmFeatureFlags
 
   override def prettyIR(source: Source, stage: Stage)(using Context): Option[Document] = stage match {
-    case Stage.Core => steps.afterCore(source).map { res => core.PrettyPrinter(Context.config.printDetailedIR()).format(res.core) }
+    case Stage.Core => steps.afterCore(source).map { res => core.PrettyPrinter(Context.config.debug()).format(res.core) }
     case Stage.CPS => None
     case Stage.Machine => steps.afterMachine(source).map { res => machine.PrettyPrinter.format(res.program) }
     case Stage.Target => steps.afterLLVM(source).map { res => pretty(res) }

From 8630bc9ec0e7bd7e804b459fde43001af2298bc3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Mon, 15 Dec 2025 13:45:45 +0100
Subject: [PATCH 10/11] Fix TestRenamerTests

---
 .../src/test/scala/effekt/core/TestRenamerTests.scala    | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala b/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
index 9b0357c7f5..0f5b459b33 100644
--- a/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/core/TestRenamerTests.scala
@@ -31,7 +31,7 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |def _renamed_0() = {
+        |def foo_renamed_0() = {
         |  return (bar: (Int) => Int @ {})(baz: Int)
         |}
         |""".stripMargin
@@ -118,13 +118,12 @@ class TestRenamerTests extends CoreTests {
         |}
         |
         |def foo_renamed_2() = {
-        |  12 match {
+        |  12 match[Int] {
         |    X : { (aa_renamed_3: Int, bb_renamed_4: Int) =>
         |      return aa_renamed_3: Int
         |    }
         |  }
-        |}
-        |""".stripMargin
+        |}""".stripMargin
     assertRenamedTo(input, expected)
   }
 
@@ -139,7 +138,7 @@ class TestRenamerTests extends CoreTests {
     val expected =
       """module main
         |
-        |def foo_renamed_0['A_renamed_1](a_renamed_2: A_renamed_1) = {
+        |def foo_renamed_0['A_renamed_1](a_renamed_2: Identity[A_renamed_1]) = {
         |  return a_renamed_2: Identity[A_renamed_1]
         |}
         |""".stripMargin

From 4f5d6b6674c6cdebb7af6b1c7da5144066a6f9e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim=20S=C3=BCberkr=C3=BCb?= <dev@timsueberkrueb.io>
Date: Tue, 16 Dec 2025 16:34:54 +0100
Subject: [PATCH 11/11] Always print internal Barendregt id

---
 .../shared/src/main/scala/effekt/core/PrettyPrinter.scala  | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
index b740574c14..1f3f9c82b4 100644
--- a/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
+++ b/effekt/shared/src/main/scala/effekt/core/PrettyPrinter.scala
@@ -9,7 +9,7 @@ import kiama.output.PrettyPrinterTypes.Document
 import scala.language.implicitConversions
 import effekt.symbols.{ Name, Wildcard, builtins }
 
-class PrettyPrinter(printDetails: Boolean) extends ParenPrettyPrinter {
+class PrettyPrinter(printDetails: Boolean, printInternalIds: Boolean = true) extends ParenPrettyPrinter {
   override val defaultIndent = 2
 
   def format(t: ModuleDecl): Document =
@@ -124,7 +124,7 @@ class PrettyPrinter(printDetails: Boolean) extends ParenPrettyPrinter {
     // In reparsable mode, we just show the string part, which should be freshened by the TestRenamer before printing.
     // The TestRenamer does not rename the Barendregt id because that would violate the internal invariant of having
     // just a single global Barendregt namespace.
-    builtins.coreBuiltinSymbolToString(s).getOrElse(if printDetails then s.name.name else s.show)
+    builtins.coreBuiltinSymbolToString(s).getOrElse(if printInternalIds then s.show else s.name.name)
   }
 
   def toDoc(e: Expr): Doc = e match {
@@ -370,9 +370,8 @@ class PrettyPrinter(printDetails: Boolean) extends ParenPrettyPrinter {
 
 /**
  * Instance of PrettyPrinter that produces output that can be parsed back by the core parser.
- * This can be enabled using the `--debug` command line flag.
  */
-object ReparsablePrettyPrinter extends PrettyPrinter(true) {}
+object ReparsablePrettyPrinter extends PrettyPrinter(true, false) {}
 
 /**
  * Instance of PrettyPrinter that produces less verbose, more human-readable output.