A Hugo incarnation of the blog.
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

96 lines
3.1 KiB

#include "type_env.hpp"
#include "type.hpp"
#include "error.hpp"
#include <cassert>
void type_env::find_free(const type_mgr& mgr, std::set<std::string>& into) const {
if(parent != nullptr) parent->find_free(mgr, into);
for(auto& binding : names) {
mgr.find_free(binding.second.type, into);
}
}
void type_env::find_free_except(const type_mgr& mgr, const group& avoid,
std::set<std::string>& into) const {
if(parent != nullptr) parent->find_free(mgr, into);
for(auto& binding : names) {
if(avoid.members.find(binding.first) != avoid.members.end()) continue;
mgr.find_free(binding.second.type, into);
}
}
type_scheme_ptr type_env::lookup(const std::string& name) const {
auto it = names.find(name);
if(it != names.end()) return it->second.type;
if(parent) return parent->lookup(name);
return nullptr;
}
bool type_env::is_global(const std::string& name) const {
auto it = names.find(name);
if(it != names.end()) return it->second.vis == visibility::global;
if(parent) return parent->is_global(name);
return false;
}
void type_env::set_mangled_name(const std::string& name, const std::string& mangled) {
auto it = names.find(name);
// Can't set mangled name for non-existent variable.
assert(it != names.end());
// Local names shouldn't need mangling.
assert(it->second.vis == visibility::global);
it->second.mangled_name = mangled;
}
const std::string& type_env::get_mangled_name(const std::string& name) const {
auto it = names.find(name);
if(it != names.end()) {
assert(it->second.mangled_name);
return *it->second.mangled_name;
}
assert(parent != nullptr);
return parent->get_mangled_name(name);
}
type_ptr type_env::lookup_type(const std::string& name) const {
auto it = type_names.find(name);
if(it != type_names.end()) return it->second;
if(parent) return parent->lookup_type(name);
return nullptr;
}
void type_env::bind(const std::string& name, type_ptr t, visibility v) {
type_scheme_ptr new_scheme(new type_scheme(std::move(t)));
names[name] = variable_data(std::move(new_scheme), v, std::nullopt);
}
void type_env::bind(const std::string& name, type_scheme_ptr t, visibility v) {
names[name] = variable_data(std::move(t), v, "");
}
void type_env::bind_type(const std::string& type_name, type_ptr t) {
if(lookup_type(type_name) != nullptr)
throw type_error("redefinition of type");
type_names[type_name] = t;
}
void type_env::generalize(const std::string& name, const group& grp, type_mgr& mgr) {
auto names_it = names.find(name);
assert(names_it != names.end());
assert(names_it->second.type->forall.size() == 0);
std::set<std::string> free_in_type;
std::set<std::string> free_in_env;
mgr.find_free(names_it->second.type->monotype, free_in_type);
find_free_except(mgr, grp, free_in_env);
for(auto& free : free_in_type) {
if(free_in_env.find(free) != free_in_env.end()) continue;
names_it->second.type->forall.push_back(free);
}
}
type_env_ptr type_scope(type_env_ptr parent) {
return type_env_ptr(new type_env(std::move(parent)));
}