wip: migrate examples

GoldsteinE · GoldsteinE · commit af9fee8b4a87 · 2026-07-02T23:37:24.000+03:00
diff --git a/examples/conditional/main.cpp b/examples/conditional/main.cpp
@@ -31,8 +31,8 @@ int main() {
     s.push(KVPair{key.to_owned(), static_cast<KVPairValue_T>(value)});
   }
   auto it = s.iter();
-  for (auto next = it.next(); next.matches_Some(); next = it.next()) {
-    auto pair = next.unwrap();
+  for (auto next = it.next(); auto some = Option<rust::Ref<KVPair>>::Some::match(next); next = it.next()) {
+    rust::Ref<KVPair> pair = some->f0;
     rust::Ref<rust::std::string::String> key = pair.key;
     KVPairValue_T value = pair.value;
     std::cout << "KVPair(size = " << KVPair::self_size()
diff --git a/examples/conditional/main.zng b/examples/conditional/main.zng
@@ -51,29 +51,29 @@ mod ::std {
     type option::Option<usize> {
         #layout(size = 16, align = 8);
 
-        constructor None;
-        constructor Some(usize);
-
-        fn unwrap(self) -> usize;
+        variant None {}
+        variant Some {
+            field 0 (offset = auto, type = usize);
+        }
     }
 
     type option::Option<crate::KeyValuePair> {
         #layout(size = 32, align = 8);
 
-        constructor None;
-        constructor Some(crate::KeyValuePair);
-
-        fn unwrap(self) -> crate::KeyValuePair;
+        variant None {}
+        variant Some {
+            field 0 (offset = auto, type = crate::KeyValuePair);
+        }
     }
 
     type option::Option<&crate::KeyValuePair> {
         #layout(size = 8, align = 8);
         wellknown_traits(Copy);
 
-        constructor None;
-        constructor Some(&crate::KeyValuePair);
-
-        fn unwrap(self) -> &crate::KeyValuePair;
+        variant None {}
+        variant Some {
+            field 0 (offset = auto, type = &crate::KeyValuePair);
+        }
     }
 
 
diff --git a/examples/memory_management/main.cpp b/examples/memory_management/main.cpp
@@ -119,10 +119,10 @@ int main() {
   }
   std::cout << "Checkpoint 35" << std::endl;
   {
-    auto p1 = Option<PrintOnDrop>::Some(
+    Option<PrintOnDrop> p1 = Option<PrintOnDrop>::Some(
         PrintOnDrop("option_A"_rs));
     std::cout << "Checkpoint 36" << std::endl;
-    auto p2 = Option<PrintOnDrop>::Some(
+    Option<PrintOnDrop> p2 = Option<PrintOnDrop>::Some(
         PrintOnDrop("option_B"_rs));
     std::cout << "Checkpoint 37" << std::endl;
     p2.take();
@@ -135,7 +135,7 @@ int main() {
     rust::Ref<rust::Str> elems[3] = {"elem1"_rs, "elem2"_rs, "elem3"_rs};
     int i = 0;
     auto iter = rust::std::iter::from_fn(
-        rust::Box<rust::Dyn<rust::Fn<Option<PrintOnDrop>>>>::make_box([&] {
+        rust::Box<rust::Dyn<rust::Fn<Option<PrintOnDrop>>>>::make_box([&]() -> Option<PrintOnDrop> {
           if (i == 3) {
             return Option<PrintOnDrop>::None();
           }
diff --git a/examples/memory_management/main.zng b/examples/memory_management/main.zng
@@ -71,8 +71,10 @@ mod ::std {
         type Option<crate::PrintOnDrop> {
             #layout(size = 16, align = 8);
 
-            constructor Some(crate::PrintOnDrop);
-            constructor None;
+            variant None {}
+            variant Some {
+                field 0 (offset = auto, type = crate::PrintOnDrop);
+            }
 
             fn take(&mut self) -> Option<crate::PrintOnDrop>;
         }
diff --git a/examples/multiple_modules/processor/processor.zng b/examples/multiple_modules/processor/processor.zng
@@ -12,7 +12,9 @@ type crate::Processor {
 type ::std::option::Option<crate::Processor> {
     #layout(size = 1, align = 1);
 
-    constructor None;
-    constructor Some(crate::Processor);
-    fn unwrap(self) -> crate::Processor;   
+    variant None {}
+    variant Some {
+        field 0 (offset = auto, type = crate::Processor);
+    }
+    fn unwrap(self) -> crate::Processor;
 }
diff --git a/examples/multiple_modules/receiver/receiver.zng b/examples/multiple_modules/receiver/receiver.zng
@@ -11,7 +11,9 @@ type crate::Receiver {
 type ::std::option::Option<crate::Receiver> {
     #layout(size = 16, align = 8);
 
-    constructor None;
-    constructor Some(crate::Receiver);
-    fn unwrap(self) -> crate::Receiver;   
+    variant None {}
+    variant Some {
+        field 0 (offset = auto, type = crate::Receiver);
+    }
+    fn unwrap(self) -> crate::Receiver;
 }
diff --git a/examples/regression_test2/main.zng b/examples/regression_test2/main.zng
@@ -12,8 +12,8 @@ type crate::Dispatcher {
 
 type ::core::task::Poll<()> {
     #layout(size = 1, align = 1);
-    constructor Ready(());
-    constructor Pending;
+    variant Ready { non_exhaustive; }
+    variant Pending {}
 
     fn is_ready(&self) -> bool;
     fn is_pending(&self) -> bool;
diff --git a/examples/rustyline/main.cpp b/examples/rustyline/main.cpp
@@ -14,10 +14,10 @@ int main() {
     auto r = editor.readline(">>> "_rs);
     if (r.is_err()) {
       auto e = r.unwrap_err();
-      if (e.matches_Eof()) {
+      if (rust::rustyline::error::ReadlineError::Eof::check(e)) {
         std::cout << "CTRL-D" << std::endl;
       }
-      if (e.matches_Interrupted()) {
+      if (rust::rustyline::error::ReadlineError::Interrupted::check(e)) {
         std::cout << "CTRL-C" << std::endl;
       }
       break;
diff --git a/examples/rustyline/main.zng b/examples/rustyline/main.zng
@@ -35,9 +35,10 @@ mod ::rustyline {
 
     type error::ReadlineError {
         #heap_allocated;
+        non_exhaustive;
 
-        constructor Interrupted;
-        constructor Eof;
+        variant Interrupted {}
+        variant Eof {}
     }
 
     type Result<DefaultEditor> {
diff --git a/examples/simple/expected_output.txt b/examples/simple/expected_output.txt
@@ -1,7 +1,7 @@
 17
 s[2] = 7
 
-thread panicked at examples/simple/src/generated.rs:351:40:
+thread panicked at examples/simple/src/generated.rs:375:40:
 called `Option::unwrap()` on a `None` value
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 s[4] = Rust panic happened
diff --git a/examples/simple/main.cpp b/examples/simple/main.cpp
@@ -23,11 +23,11 @@ class VectorIterator : public rust::std::iter::Iterator<T> {
 
   Option<T> next() override {
     if (pos >= vec.size()) {
-      return Option<T>::None();
+      return typename Option<T>::None();
     }
     T value = vec[pos++];
     // You can construct Rust enum with fields in C++
-    return Option<T>::Some(value);
+    return typename Option<T>::Some(value);
   }
 };
 
diff --git a/examples/simple/main.zng b/examples/simple/main.zng
@@ -9,8 +9,10 @@ mod ::std {
         #layout(size = 8, align = 4);
         wellknown_traits(Copy);
 
-        constructor None;
-        constructor Some(i32);
+        variant None {}
+        variant Some {
+            field 0 (offset = auto, type = i32);
+        }
 
         fn unwrap(self) -> i32;
     }
diff --git a/examples/simple_import/bar.zng b/examples/simple_import/bar.zng
@@ -15,8 +15,10 @@ mod ::std {
     type option::Option<::std::string::String> {
         #layout(size = 24, align = 8);
 
-        constructor None;
-        constructor Some(::std::string::String);
+        variant None {}
+        variant Some {
+            field 0 (offset = auto, type = ::std::string::String);
+        }
 
         fn is_some(&self) -> bool;
         fn is_none(&self) -> bool;
diff --git a/examples/simple_import/expected_output.txt b/examples/simple_import/expected_output.txt
@@ -1,5 +1,5 @@
 foo(): Creating a Rust Vec<i32>
-  Vec contents: [main.cpp:13] numbers = [
+  Vec contents: [main.cpp:17] numbers = [
     10,
     20,
     30,
@@ -10,4 +10,4 @@ foo(): Creating a Rust Vec<i32>
 bar(): Creating Rust Option<String>
   some_value.is_some(): 1
   none_value.is_none(): 1
-  Unwrapped string: [main.cpp:33] unwrapped_string = ""
+  Unwrapped string: [main.cpp:37] unwrapped_string = ""
diff --git a/examples/simple_import/main.cpp b/examples/simple_import/main.cpp
@@ -1,9 +1,13 @@
 #include <iostream>
 #include "generated.h"
 
+template<class T> using Vec = rust::std::vec::Vec<T>;
+template<class T> using Option = rust::std::option::Option<T>;
+using String = rust::std::string::String;
+
 // External function declarations from foo.cpp and bar.cpp
-extern rust::std::vec::Vec<int32_t> foo();
-extern rust::std::option::Option<rust::std::string::String> bar();
+extern Vec<int32_t> foo();
+extern Option<String> bar();
 
 int main() {
     // Get Vec<i32> from foo() and demonstrate both imported and extended APIs
@@ -21,7 +25,7 @@ int main() {
     // Get Option<String> from bar() and demonstrate both imported and extended APIs
     std::cout << "bar(): Creating Rust Option<String>" << std::endl;
     auto some_value = bar();
-    auto none_value = rust::std::option::Option<rust::std::string::String>::None();
+    Option<String> none_value = Option<String>::None();
 
     // Use imported APIs from bar.zng
     std::cout << "  some_value.is_some(): " << some_value.is_some() << std::endl;
diff --git a/examples/simple_import/main.zng b/examples/simple_import/main.zng
@@ -27,9 +27,11 @@ mod ::std {
     type option::Option<::std::string::String> {
         #layout(size = 24, align = 8);
 
-        // Inherited constructors and methods from bar.zng (automatically merged)
-        constructor None;
-        constructor Some(::std::string::String);
+        // Inherited variants and methods from bar.zng (automatically merged)
+        variant None {}
+        variant Some {
+            field 0 (offset = auto, type = ::std::string::String);
+        }
         fn is_some(&self) -> bool;
         fn is_none(&self) -> bool;
 
diff --git a/examples/tutorial-wasm32/main.cpp b/examples/tutorial-wasm32/main.cpp
@@ -23,11 +23,11 @@ class VectorIterator : public rust::std::iter::Iterator<T> {
 
   Option<T> next() override {
     if (pos >= vec.size()) {
-      return Option<T>::None();
+      return typename Option<T>::None();
     }
     T value = vec[pos++];
     // You can construct Rust enum with fields in C++
-    return Option<T>::Some(value);
+    return typename Option<T>::Some(value);
   }
 };
 
diff --git a/examples/tutorial-wasm32/main32.zng b/examples/tutorial-wasm32/main32.zng
@@ -7,8 +7,10 @@ mod ::std {
         #layout(size = 8, align = 4);
         wellknown_traits(Copy);
 
-        constructor None;
-        constructor Some(i32);
+        variant None {}
+        variant Some {
+            field 0 (offset = auto, type = i32);
+        }
 
         fn unwrap(self) -> i32;
     }
diff --git a/examples/tutorial_cpp/main.zng b/examples/tutorial_cpp/main.zng
@@ -36,8 +36,11 @@ type crate::Item {
 
 type ::std::fmt::Result {
     #layout(size = 1, align = 1);
+    non_exhaustive;
 
-    constructor Ok(());
+    variant Ok {
+        non_exhaustive;
+    }
 }
 
 type ::std::fmt::Formatter {

Original file line number	Diff line number	Diff line change
`@@ -14,10 +14,10 @@ int main() {`
`14`	`14`	`auto r = editor.readline(">>> "_rs);`
`15`	`15`	`if (r.is_err()) {`
`16`	`16`	`auto e = r.unwrap_err();`
`17`		`- if (e.matches_Eof()) {`
	`17`	`+ if (rust::rustyline::error::ReadlineError::Eof::check(e)) {`
`18`	`18`	`std::cout << "CTRL-D" << std::endl;`
`19`	`19`	`}`
`20`		`- if (e.matches_Interrupted()) {`
	`20`	`+ if (rust::rustyline::error::ReadlineError::Interrupted::check(e)) {`
`21`	`21`	`std::cout << "CTRL-C" << std::endl;`
`22`	`22`	`}`
`23`	`23`	`break;`
Original file line number	Diff line number	Diff line change
`@@ -1,7 +1,7 @@`
`1`	`1`	`17`
`2`	`2`	`s[2] = 7`
`3`	`3`
`4`		`-thread panicked at examples/simple/src/generated.rs:351:40:`
	`4`	`+thread panicked at examples/simple/src/generated.rs:375:40:`
`5`	`5`	called `Option::unwrap()` on a `None` value
`6`	`6`	note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
`7`	`7`	`s[4] = Rust panic happened`