[cpp] method names are now mangled within try_find_function and metho…

…d_call, meaning that you can no longer try calling a method as if it were a free function (which would pass checks, but cause an llvm error coz no `this` parameter). this also means methods can have the same name as free functions without causing conflicts.

cpp/src/codegen.cpp

@@ -975,11 +975,12 @@ namespace code
 	value function_call(const data& d, ast::function_call payload)
 	{
 		const semal::function_t* func = d.state.try_find_function(payload.function_name);
+		d.ctx.assert_that(func != nullptr, error_code::codegen, "call to undefined function \"{}\"", payload.function_name);
+		d.ctx.assert_that(!func->is_method, error_code::codegen, "call to method as \"{}.{}\" if it were a free function.", func->method_owner_struct_name, payload.function_name);
 		if(func->is_builtin)
 		{
 			return codegen_builtin(d, payload, try_find_builtin(payload.function_name));
 		}
-		d.ctx.assert_that(func != nullptr, error_code::codegen, "call to undefined function \"{}\"", payload.function_name);
 		auto* llvm_func = static_cast<llvm::Function*>(func->userdata);
 		d.ctx.assert_that(llvm_func != nullptr, error_code::ice, "function \"{}\" had a nullptr userdata, implying it has not been codegen'd", payload.function_name);
 		std::vector<llvm::Value*> llvm_params = {};

cpp/src/semal.cpp

@@ -174,7 +174,7 @@ namespace semal
 		{
 			for(const auto& [mthname, mthdata] : structdata.methods)
 			{
-				if(mthname == name)
+				if(mangle_method_name(mthname) == name)
 				{
 					return &mthdata;
 				}
@@ -206,6 +206,10 @@ namespace semal
 				const std::string& function_name = std::get<ast::function_definition>(ancestor.payload).func_name;
 				const function_t* found_func = this->try_find_function(function_name.c_str());
 				if(found_func == nullptr)
+				{
+					found_func = this->try_find_function(semal::mangle_method_name(function_name));
+				}
+				if(found_func == nullptr)
 				{
 					diag::ice("at: {}: internal compiler error: found a parent function of an AST node (named \"{}\"), but could not then retrieve the function data from semantic analysis state.", ancestor.meta.to_string(), function_name);
 				}
@@ -485,6 +489,11 @@ namespace semal
 		return ret;
 	}
 
+	std::string mangle_method_name(std::string method_name)
+	{
+		return "__method_" + method_name;
+	}
+
 	type output::get_type_from_payload(const ast::node::payload_t& payload, const ast& tree, const ast::path_t& path) const
 	{
 		return generic({.state = const_cast<output&>(*this), .path = path, .tree = tree}, payload);

cpp/src/semal.hpp

@@ -34,6 +34,7 @@ namespace semal
 			}
 		}
 	};
+
 	struct local_variable_t
 	{
 		type ty;
@@ -99,6 +100,7 @@ namespace semal
 
 	output analyse_predecl(const ast& tree);
 	output analyse_full(const ast& tree, output predecl = {});
+	std::string mangle_method_name(std::string method_name);
 
 	struct state
 	{