feat: enable iterating through module functions (#220)

This commit makes a `Fucntions::iter` available, to enable iterating
through functions present in a module.

To keep changes to the public interface small, `Functions<'a>` now has
a `iter()` function that returns an opaque iterator.

Signed-off-by: Victor Adossi <vadossi@cosmonic.com>

src/ir/component.rs

@@ -7,7 +7,7 @@ use crate::ir::helpers::{
     print_core_type,
 };
 use crate::ir::id::{CustomSectionID, FunctionID, GlobalID, ModuleID};
-use crate::ir::module::{Iter, Module};
+use crate::ir::module::Module;
 use crate::ir::section::ComponentSection;
 use crate::ir::wrappers::{
     add_to_namemap, convert_component_type, convert_instance_type, convert_module_type_declaration,

src/ir/module/mod.rs

@@ -890,7 +890,7 @@ impl<'a> Module<'a> {
                 &mut self.functions,
             )
         } else {
-            Self::get_mapping_generic(self.functions.iter())
+            Self::get_mapping_generic(Iter::<Function<'a>>::iter(&self.functions))
         };
         let global_mapping = if self.globals.recalculate_ids {
             Self::recalculate_ids(
@@ -1572,8 +1572,12 @@ pub trait GetID {
     fn get_id(&self) -> u32;
 }
 
+/// Facilitates iteration on types that hold `T`
 pub(crate) trait Iter<T> {
+    /// Iterate over references of `T`
     fn iter(&self) -> std::slice::Iter<'_, T>;
+
+    /// Clone and build an iterator
     fn get_into_iter(&self) -> IntoIter<T>;
 }
 

src/ir/module/module_functions.rs

@@ -235,6 +235,16 @@ pub struct Functions<'a> {
     pub(crate) recalculate_ids: bool,
 }
 
+impl<'a> Functions<'a> {
+    /// Iterate over functions present in the module
+    ///
+    /// Note: Functions returned by this iterator *may* be deleted.
+    #[must_use]
+    pub fn iter(&self) -> impl Iterator<Item = &Function<'a>> {
+        Iter::<Function<'a>>::iter(self)
+    }
+}
+
 impl<'a> Iter<Function<'a>> for Functions<'a> {
     /// Get an iterator for the functions.
     fn iter(&self) -> std::slice::Iter<'_, Function<'a>> {