Add #cpp_heap_allocated directive, deprecate #cpp_value

book/src/call_cpp_from_rust/opaque.md

@@ -9,7 +9,7 @@ There are currently 3 kinds of opaque types that `zngur` is able to represent
 These types are made available to Rust with varying sets of restrictions and tradeoffs imposed
 based on your choice
 
-For each of these types (aka. marked `#cpp_ref`, `#cpp_value`, or
+For each of these types (aka. marked `#cpp_ref`, `#cpp_heap_allocated`, or
 `#cpp_stack_owned`), `zngur` will generate a new type within `pub mod cpp {}`.
 
 This module is where all generated opaque types live
@@ -61,9 +61,12 @@ Those problem might be solved by the `extern type` language feature.
 
 ## Opaque Heap Allocated C++ Type
 
-Keeping C++ objects in Rust using heap allocation is supported with `#cpp_value` types.
+Keeping C++ objects in Rust using heap allocation is supported with `#cpp_heap_allocated` types.
 This is similar to `#cpp_ref` types. Look at the example `tutorial_cpp` for a usage example
 
+> **NOTE**: `#cpp_value` is a deprecated alias for `#cpp_heap_allocated` and will
+> emit a warning when used; new code should use `#cpp_heap_allocated`.
+
 ### Semantics of Opaque Heap Allocated Types
 
 Heap allocated types are generated as a #[repr(C)] struct to a heap allocated pointer and destructor.

book/src/tutorial.md

@@ -396,13 +396,13 @@ In the same directory, create a `main.zng` file with the following content:
 type crate::Inventory {
     #layout(size = 16, align = 8);
 
-    #cpp_value "0" "::cpp_inventory::Inventory";
+    #cpp_heap_allocated "::cpp_inventory::Inventory";
 }
 
 type crate::Item {
     #layout(size = 16, align = 8);
 
-    #cpp_value "0" "::cpp_inventory::Item";
+    #cpp_heap_allocated "::cpp_inventory::Item";
 }
 ```
 

examples/multiple_modules/aggregation/aggregation.zng

@@ -6,7 +6,7 @@ import "packet.zng";
 
 type crate::StatsAccumulator {
     #layout(size = 16, align = 8);
-    #cpp_value "0" "::cpp_stats::StatsAccumulator";
+    #cpp_heap_allocated "::cpp_stats::StatsAccumulator";
 }
 
 extern "C++" {

examples/tutorial_cpp/main.zng

@@ -25,13 +25,13 @@ type ::std::result::Result<&str, ::std::str::Utf8Error> {
 type crate::Inventory {
     #layout(size = 16, align = 8);
 
-    #cpp_value "0" "::cpp_inventory::Inventory";
+    #cpp_heap_allocated "::cpp_inventory::Inventory";
 }
 
 type crate::Item {
     #layout(size = 16, align = 8);
 
-    #cpp_value "0" "::cpp_inventory::Item";
+    #cpp_heap_allocated "::cpp_inventory::Item";
 }
 
 type ::std::fmt::Result {

zngur-cli/src/main.rs

@@ -172,7 +172,8 @@ fn main() {
                 .with_cpp_file(cpp_file)
                 .with_h_file(h_file)
                 .with_rs_file(rs_file)
-                .with_zng_header_in_place_as(zng_header_in_place);
+                .with_zng_header_in_place_as(zng_header_in_place)
+                .with_warning_sink(|w| eprintln!("{w}"));
             if let Some(cpp_namespace) = cpp_namespace {
                 zng = zng.with_cpp_namespace(&cpp_namespace);
             }

zngur-def/src/lib.rs

@@ -146,7 +146,13 @@ pub struct ZngurMethodDetails {
 }
 
 #[derive(Debug, PartialEq, Eq, Clone)]
-pub struct CppValue(pub String, pub String);
+pub struct CppHeapAllocated(pub String);
+
+#[derive(Debug)]
+pub struct CppHeapAllocatedData {
+    pub bridge_fn: String,
+    pub cpp_type: String,
+}
 
 #[derive(Debug, PartialEq, Eq, Clone)]
 pub struct CppRef(pub String);
@@ -174,7 +180,7 @@ pub struct ZngurType {
     pub constructor: Option<ZngurConstructor>,
     pub variants: Vec<ZngurVariant>,
     pub fields: Vec<ZngurField>,
-    pub cpp_value: Option<CppValue>,
+    pub cpp_heap_allocated: Option<CppHeapAllocated>,
     pub cpp_ref: Option<CppRef>,
     pub cpp_stack_owned: Option<CppStackOwned>,
 }

zngur-def/src/merge.rs

@@ -1,6 +1,6 @@
 use crate::{
-    AdditionalIncludes, ConvertPanicToException, CppRef, CppStackOwned, CppValue, LayoutPolicy,
-    ZngurConstructor, ZngurExternCppFn, ZngurExternCppImpl, ZngurField, ZngurFn,
+    AdditionalIncludes, ConvertPanicToException, CppHeapAllocated, CppRef, CppStackOwned,
+    LayoutPolicy, ZngurConstructor, ZngurExternCppFn, ZngurExternCppImpl, ZngurField, ZngurFn,
     ZngurMethodDetails, ZngurSpec, ZngurTrait, ZngurType, ZngurVariant,
 };
 
@@ -148,7 +148,8 @@ impl Merge for ZngurType {
             ));
         }
 
-        self.cpp_value.merge(&mut into.cpp_value)?;
+        self.cpp_heap_allocated
+            .merge(&mut into.cpp_heap_allocated)?;
         self.cpp_ref.merge(&mut into.cpp_ref)?;
         self.cpp_stack_owned.merge(&mut into.cpp_stack_owned)?;
 
@@ -189,14 +190,16 @@ impl Merge for ZngurTrait {
     }
 }
 
-impl Merge for CppValue {
+impl Merge for CppHeapAllocated {
     /// Writes the partial union of `self` and `into` to the latter.
     ///
-    /// There is no meaningful way to merge different CppValues, but we allow
-    /// merging the same CppValue from different sources.
+    /// There is no meaningful way to merge different CppHeapAllocated values, but we
+    /// allow merging the same CppHeapAllocated value from different sources.
     fn merge(self, into: &mut Self) -> MergeResult {
         if self != *into {
-            return Err(MergeFailure::Conflict("Cpp value mismatch".to_string()));
+            return Err(MergeFailure::Conflict(
+                "Cpp heap allocated mismatch".to_string(),
+            ));
         }
         Ok(())
     }

zngur-generator/src/cpp.rs

@@ -5,7 +5,9 @@ use std::{
 
 use indexmap::IndexMap;
 use itertools::Itertools;
-use zngur_def::{CppRef, CppStackOwned, CppValue, RustTrait, ZngurFieldData, ZngurMethodReceiver};
+use zngur_def::{
+    CppHeapAllocatedData, CppRef, CppStackOwned, RustTrait, ZngurFieldData, ZngurMethodReceiver,
+};
 
 use crate::{
     ZngurWellknownTraitData,
@@ -525,7 +527,7 @@ pub struct CppTypeDefinition {
     pub from_trait: Option<RustTrait>,
     pub from_trait_ref: Option<RustTrait>,
     pub wellknown_traits: Vec<ZngurWellknownTraitData>,
-    pub cpp_value: Option<CppValue>,
+    pub cpp_heap_allocated: Option<CppHeapAllocatedData>,
     pub cpp_ref: Option<CppRef>,
     pub cpp_stack_owned: Option<CppStackOwned>,
 }
@@ -659,7 +661,7 @@ impl Default for CppTypeDefinition {
             wellknown_traits: vec![],
             from_trait: None,
             from_trait_ref: None,
-            cpp_value: None,
+            cpp_heap_allocated: None,
             cpp_ref: None,
             cpp_stack_owned: None,
         }

zngur-generator/src/lib.rs

@@ -161,7 +161,7 @@ impl ZngurGenerator {
 "#
                 ));
             }
-            if ty_def.cpp_value.is_some() {
+            if ty_def.cpp_heap_allocated.is_some() {
                 let type_name = ty.to_string().split("::").last().unwrap().to_string();
                 cpp_mod_content.push_str(&format!(
                     r#"
@@ -325,9 +325,11 @@ impl ZngurGenerator {
                 fields,
                 methods: cpp_methods,
                 wellknown_traits,
-                cpp_value: ty_def.cpp_value.map(|mut cpp_value| {
-                    cpp_value.0 = rust_file.add_cpp_value_bridge(&ty);
-                    cpp_value
+                cpp_heap_allocated: ty_def.cpp_heap_allocated.map(|cpp_heap_allocated| {
+                    CppHeapAllocatedData {
+                        bridge_fn: rust_file.add_cpp_heap_allocated_bridge(&ty),
+                        cpp_type: cpp_heap_allocated.0,
+                    }
                 }),
                 cpp_ref: ty_def.cpp_ref,
                 cpp_stack_owned: ty_def.cpp_stack_owned,

zngur-generator/src/rust.rs

@@ -1099,9 +1099,9 @@ pub {}fn {rust_name}("#,
         mangled_name
     }
 
-    pub fn add_cpp_value_bridge(&mut self, ty: &RustType) -> String {
+    pub fn add_cpp_heap_allocated_bridge(&mut self, ty: &RustType) -> String {
         let type_name = ty.to_string().split("::").last().unwrap().to_string();
-        let mangled_name = self.mangle_name(&format!("{ty}_cpp_value"));
+        let mangled_name = self.mangle_name(&format!("{ty}_cpp_heap_allocated"));
         w!(
             self,
             r#"

zngur-generator/templates/cpp_header.sptl

@@ -78,8 +78,8 @@ extern "C" {
       uint32_t {{ discriminant }} (uint8_t* i) noexcept;
     {% endif %}
 
-    {% if let Some(cpp_value) = td.cpp_value %}
-      ::{{ self.namespace }}::ZngurCppOpaqueOwnedObject* {{ cpp_value.0 }}(uint8_t*);
+    {% if let Some(cpp_heap_allocated) = td.cpp_heap_allocated %}
+      ::{{ self.namespace }}::ZngurCppOpaqueOwnedObject* {{ cpp_heap_allocated.bridge_fn }}(uint8_t*);
     {% endif %}
 
     {% if !td.layout.is_stack_allocated() && !td.layout.is_only_by_ref() %}
@@ -368,9 +368,9 @@ namespace {{ self.namespace }} {
 
       {{ td.render_make_box(name, self.namespace, self.crate_name) }}
 
-      {% if let Some(cpp_value) = td.cpp_value %}
-          inline {{ cpp_value.1 }}& cpp() {
-              return (*{{ cpp_value.0 }}(::{{ self.namespace }}::__zngur_internal_data_ptr(*this))).as_cpp< {{ cpp_value.1 }} >();
+      {% if let Some(cpp_heap_allocated) = td.cpp_heap_allocated %}
+          inline {{ cpp_heap_allocated.cpp_type }}& cpp() {
+              return (*{{ cpp_heap_allocated.bridge_fn }}(::{{ self.namespace }}::__zngur_internal_data_ptr(*this))).as_cpp< {{ cpp_heap_allocated.cpp_type }} >();
           }
 
           inline {{ name }}(::{{ self.namespace }}::ZngurCppOpaqueOwnedObject&& o) noexcept {
@@ -382,7 +382,7 @@ namespace {{ self.namespace }} {
 
           template<typename... Args>
           static inline {{ name }} build(Args&&... args) {
-              return {{ name }}(::{{ self.namespace }}::ZngurCppOpaqueOwnedObject::build< {{ cpp_value.1 }} >(::std::forward<Args>(args)...));
+              return {{ name }}(::{{ self.namespace }}::ZngurCppOpaqueOwnedObject::build< {{ cpp_heap_allocated.cpp_type }} >(::std::forward<Args>(args)...));
           }
       {% endif %}
 
@@ -704,9 +704,9 @@ namespace {{ self.namespace }} {
 
     {{ td.render_make_box_ref(td.ty.path.name(), self.namespace, self.crate_name) }}
 
-    {% if let Some(cpp_value) = td.cpp_value %}
-      inline {{ cpp_value.1 }}& cpp() {
-          return (*{{ cpp_value.0 }}(reinterpret_cast<uint8_t*>(__zngur_data))).as_cpp< {{ cpp_value.1 }} >();
+    {% if let Some(cpp_heap_allocated) = td.cpp_heap_allocated %}
+      inline {{ cpp_heap_allocated.cpp_type }}& cpp() {
+          return (*{{ cpp_heap_allocated.bridge_fn }}(reinterpret_cast<uint8_t*>(__zngur_data))).as_cpp< {{ cpp_heap_allocated.cpp_type }} >();
       }
     {% endif %}
 
@@ -928,9 +928,9 @@ namespace {{ self.namespace }} {
 
     {{ td.render_make_box_ref_only(td.ty.path.name(), self.namespace, self.crate_name) }}
 
-    {% if let Some(cpp_value) = td.cpp_value %}
-      inline {{ cpp_value.1 }}& cpp() {
-        return (*{{ cpp_value.0 }}(reinterpret_cast<uint8_t*>(__zngur_data))).as_cpp< {{ cpp_value.1 }} >();
+    {% if let Some(cpp_heap_allocated) = td.cpp_heap_allocated %}
+      inline {{ cpp_heap_allocated.cpp_type }}& cpp() {
+        return (*{{ cpp_heap_allocated.bridge_fn }}(reinterpret_cast<uint8_t*>(__zngur_data))).as_cpp< {{ cpp_heap_allocated.cpp_type }} >();
       }
     {% endif %}
 

zngur-parser/Cargo.toml

@@ -13,8 +13,8 @@ license.workspace = true
 ariadne = "0.3.0"
 chumsky = { version = "=1.0.0-alpha.8", features = [] }
 itertools = "0.11"
+strip-ansi-escapes = "0.2.0"
 zngur-def = { version = "=0.11.0", path = "../zngur-def" }
 
 [dev-dependencies]
 expect-test = "1.4.1"
-strip-ansi-escapes = "0.2.0"