Partial comparisons of types/paths to speed up impl searches

1 files changed, 23 insertions, 1 deletions

diff --git a/src/ast/ast.cpp b/src/ast/ast.cpp
index b8e6d381..4c400a47 100644
--- a/src/ast/ast.cpp
+++ b/src/ast/ast.cpp
@@ -80,7 +80,29 @@ Impl Impl::make_concrete(const ::std::vector<TypeRef>& types) const
 

 ::rust::option<Impl&> Impl::matches(const Path& trait, const TypeRef& type)

 {

-    DEBUG("this = " << *this);

+    //DEBUG("this = " << *this);

+    

+    // 1. Check the type/trait counting parameters as wildcards (but flagging if one was seen)

+    //  > If that fails, just early return

+    int trait_match = m_trait.equal_no_generic(trait);

+    if( trait_match < 0 )

+        return ::rust::option<Impl&>();

+    DEBUG("Trait " << trait << " matches " << trait_match);

+    int type_match = m_type.equal_no_generic(type);

+    if( type_match < 0 )

+        return ::rust::option<Impl&>();

+    DEBUG("Type " << type << " matches " << type_match);

+    // 2. If a parameter was seen, do the more expensive generic checks

+    //  > Involves checking that parameters are valid

+    if( trait_match > 0 )

+    {

+        throw CompileError::Todo("Generic-ised match of impl trait");

+    }

+    if( type_match > 0 )

+    {

+        throw CompileError::Todo("Generic-ised match of impl type");

+    }

+    // 3. Return success

     

     if( m_params.ty_params().size() > 0 )

     {