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#include "ast.hpp"
#include <ostream>
#include "error.hpp"
static void print_indent(int n, std::ostream& to) {
while(n--) to << " ";
}
type_ptr ast::typecheck_common(type_mgr& mgr, const type_env& env) {
node_type = typecheck(mgr, env);
return node_type;
}
void ast::resolve_common(const type_mgr& mgr) {
type_var* var;
type_ptr resolved_type = mgr.resolve(node_type, var);
if(var) throw type_error("ambiguously typed program");
resolve(mgr);
node_type = std::move(resolved_type);
}
void ast_int::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "INT: " << value << std::endl;
}
type_ptr ast_int::typecheck(type_mgr& mgr, const type_env& env) const {
return type_ptr(new type_base("Int"));
}
void ast_int::resolve(const type_mgr& mgr) const {
}
void ast_int::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
into.push_back(instruction_ptr(new instruction_pushint(value)));
}
void ast_lid::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "LID: " << id << std::endl;
}
type_ptr ast_lid::typecheck(type_mgr& mgr, const type_env& env) const {
return env.lookup(id);
}
void ast_lid::resolve(const type_mgr& mgr) const {
}
void ast_lid::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
into.push_back(instruction_ptr(
env->has_variable(id) ?
(instruction*) new instruction_push(env->get_offset(id)) :
(instruction*) new instruction_pushglobal(id)));
}
void ast_uid::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "UID: " << id << std::endl;
}
type_ptr ast_uid::typecheck(type_mgr& mgr, const type_env& env) const {
return env.lookup(id);
}
void ast_uid::resolve(const type_mgr& mgr) const {
}
void ast_uid::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
into.push_back(instruction_ptr(new instruction_pushglobal(id)));
}
void ast_binop::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "BINOP: " << op_name(op) << std::endl;
left->print(indent + 1, to);
right->print(indent + 1, to);
}
type_ptr ast_binop::typecheck(type_mgr& mgr, const type_env& env) const {
type_ptr ltype = left->typecheck_common(mgr, env);
type_ptr rtype = right->typecheck_common(mgr, env);
type_ptr ftype = env.lookup(op_name(op));
if(!ftype) throw type_error(std::string("unknown binary operator ") + op_name(op));
type_ptr return_type = mgr.new_type();
type_ptr arrow_one = type_ptr(new type_arr(rtype, return_type));
type_ptr arrow_two = type_ptr(new type_arr(ltype, arrow_one));
mgr.unify(arrow_two, ftype);
return return_type;
}
void ast_binop::resolve(const type_mgr& mgr) const {
left->resolve_common(mgr);
right->resolve_common(mgr);
}
void ast_binop::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
right->compile(env, into);
left->compile(env_ptr(new env_offset(1, env)), into);
into.push_back(instruction_ptr(new instruction_pushglobal(op_action(op))));
into.push_back(instruction_ptr(new instruction_mkapp()));
into.push_back(instruction_ptr(new instruction_mkapp()));
}
void ast_app::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "APP:" << std::endl;
left->print(indent + 1, to);
right->print(indent + 1, to);
}
type_ptr ast_app::typecheck(type_mgr& mgr, const type_env& env) const {
type_ptr ltype = left->typecheck_common(mgr, env);
type_ptr rtype = right->typecheck_common(mgr, env);
type_ptr return_type = mgr.new_type();
type_ptr arrow = type_ptr(new type_arr(rtype, return_type));
mgr.unify(arrow, ltype);
return return_type;
}
void ast_app::resolve(const type_mgr& mgr) const {
left->resolve_common(mgr);
right->resolve_common(mgr);
}
void ast_app::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
right->compile(env, into);
left->compile(env_ptr(new env_offset(1, env)), into);
into.push_back(instruction_ptr(new instruction_mkapp()));
}
void ast_case::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "CASE: " << std::endl;
for(auto& branch : branches) {
print_indent(indent + 1, to);
branch->pat->print(to);
to << std::endl;
branch->expr->print(indent + 2, to);
}
}
type_ptr ast_case::typecheck(type_mgr& mgr, const type_env& env) const {
type_var* var;
type_ptr case_type = mgr.resolve(of->typecheck_common(mgr, env), var);
type_ptr branch_type = mgr.new_type();
for(auto& branch : branches) {
type_env new_env = env.scope();
branch->pat->match(case_type, mgr, new_env);
type_ptr curr_branch_type = branch->expr->typecheck_common(mgr, new_env);
mgr.unify(branch_type, curr_branch_type);
}
case_type = mgr.resolve(case_type, var);
if(!dynamic_cast<type_data*>(case_type.get())) {
throw type_error("attempting case analysis of non-data type");
}
return branch_type;
}
void ast_case::resolve(const type_mgr& mgr) const {
of->resolve_common(mgr);
for(auto& branch : branches) {
branch->expr->resolve_common(mgr);
}
}
void ast_case::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
type_data* type = dynamic_cast<type_data*>(of->node_type.get());
of->compile(env, into);
into.push_back(instruction_ptr(new instruction_eval()));
instruction_jump* jump_instruction = new instruction_jump();
into.push_back(instruction_ptr(jump_instruction));
for(auto& branch : branches) {
std::vector<instruction_ptr> branch_instructions;
pattern_var* vpat;
pattern_constr* cpat;
if((vpat = dynamic_cast<pattern_var*>(branch->pat.get()))) {
branch->expr->compile(env_ptr(new env_offset(1, env)), branch_instructions);
for(auto& constr_pair : type->constructors) {
if(jump_instruction->tag_mappings.find(constr_pair.second.tag) !=
jump_instruction->tag_mappings.end())
break;
jump_instruction->tag_mappings[constr_pair.second.tag] =
jump_instruction->branches.size();
}
jump_instruction->branches.push_back(std::move(branch_instructions));
} else if((cpat = dynamic_cast<pattern_constr*>(branch->pat.get()))) {
env_ptr new_env = env;
for(auto it = cpat->params.rbegin(); it != cpat->params.rend(); it++) {
new_env = env_ptr(new env_var(*it, new_env));
}
branch_instructions.push_back(instruction_ptr(new instruction_split()));
branch->expr->compile(new_env, branch_instructions);
branch_instructions.push_back(instruction_ptr(new instruction_slide(
cpat->params.size())));
int new_tag = type->constructors[cpat->constr].tag;
if(jump_instruction->tag_mappings.find(new_tag) !=
jump_instruction->tag_mappings.end())
throw type_error("technically not a type error: duplicate pattern");
jump_instruction->tag_mappings[new_tag] =
jump_instruction->branches.size();
jump_instruction->branches.push_back(std::move(branch_instructions));
}
}
for(auto& constr_pair : type->constructors) {
if(jump_instruction->tag_mappings.find(constr_pair.second.tag) ==
jump_instruction->tag_mappings.end())
throw type_error("non-total pattern");
}
}
void pattern_var::print(std::ostream& to) const {
to << var;
}
void pattern_var::match(type_ptr t, type_mgr& mgr, type_env& env) const {
env.bind(var, t);
}
void pattern_constr::print(std::ostream& to) const {
to << constr;
for(auto& param : params) {
to << " " << param;
}
}
void pattern_constr::match(type_ptr t, type_mgr& mgr, type_env& env) const {
type_ptr constructor_type = env.lookup(constr);
if(!constructor_type) {
throw type_error(std::string("pattern using unknown constructor ") + constr);
}
for(int i = 0; i < params.size(); i++) {
type_arr* arr = dynamic_cast<type_arr*>(constructor_type.get());
if(!arr) throw type_error("too many parameters in constructor pattern");
env.bind(params[i], arr->left);
constructor_type = arr->right;
}
mgr.unify(t, constructor_type);
}