// Both sub and super are nominal types.
static bool is_nominal_sub_nominal(ast_t* sub, ast_t* super)
{
if(!is_sub_cap_and_ephemeral(sub, super))
return false;
ast_t* sub_def = (ast_t*)ast_data(sub);
ast_t* super_def = (ast_t*)ast_data(super);
// If we are the same nominal type, our typeargs must be the same.
if(sub_def == super_def)
return is_eq_typeargs(sub, super);
switch(ast_id(super_def))
{
case TK_PRIMITIVE:
case TK_CLASS:
case TK_ACTOR:
// If we aren't the same type, we can't be a subtype of a concrete type.
return false;
case TK_INTERFACE:
// Check for an explicit provide or a structural subtype.
return is_nominal_sub_trait(sub, super) ||
is_nominal_sub_interface(sub, super);
case TK_TRAIT:
// Check for a nominal subtype.
return is_nominal_sub_trait(sub, super);
default: {}
}
return false;
}
static bool is_nominal_sub_nominal(ast_t* sub, ast_t* super,
errorframe_t* errors)
{
// N k <: N' k'
ast_t* super_def = (ast_t*)ast_data(super);
switch(ast_id(super_def))
{
case TK_PRIMITIVE:
case TK_STRUCT:
case TK_CLASS:
case TK_ACTOR:
return is_nominal_sub_entity(sub, super, errors);
case TK_INTERFACE:
return is_nominal_sub_interface(sub, super, errors);
case TK_TRAIT:
return is_nominal_sub_trait(sub, super, errors);
default: {}
}
assert(0);
return false;
}
