xlang/bootstrap/typecheck.cc

111 lines
3.3 KiB
C++

#include <typecheck.hh>
namespace xlang {
bool TypeCheckVisitor::inScope(const std::string &name) {
for (auto it = scope.end() - 1;; it--) {
if (it->find(name) != it->end()) {
return true;
}
if (it == scope.begin()) {
break;
}
}
return false;
}
TypeCheckVisitor::TypeCheckVisitor(ErrorListener &errorlistener)
: errorlistener{errorlistener} {}
std::any TypeCheckVisitor::visitFile(xlangParser::FileContext *ctx) {
for (auto function : ctx->function()) {
auto token = function->Identifier()->getSymbol();
auto name = token->getText();
if (function_arity.find(name) != function_arity.end()) {
errorlistener.typeError(token->getLine(), token->getCharPositionInLine(),
"duplicate function '" + name + "'");
continue;
}
if (auto arg_list = function->argumentList()) {
function_arity[name] = arg_list->Identifier().size();
} else {
function_arity[name] = 0;
}
}
visitChildren(ctx);
return {};
}
std::any TypeCheckVisitor::visitFunction(xlangParser::FunctionContext *ctx) {
scope.emplace_back();
if (auto arg_list = ctx->argumentList()) {
for (const auto arg : arg_list->Identifier()) {
scope.back().emplace(arg->getSymbol()->getText());
}
}
visitBlock(ctx->block());
scope.pop_back();
return {};
}
std::any TypeCheckVisitor::visitBlock(xlangParser::BlockContext *ctx) {
scope.emplace_back();
visitChildren(ctx);
scope.pop_back();
return {};
}
std::any TypeCheckVisitor::visitStatement(xlangParser::StatementContext *ctx) {
if (auto identifier = ctx->Identifier()) {
visitExpr(ctx->expr());
scope.back().emplace(identifier->getSymbol()->getText());
return {};
}
visitChildren(ctx);
return {};
}
std::any TypeCheckVisitor::visitFactor(xlangParser::FactorContext *ctx) {
if (auto identifier = ctx->Identifier()) {
auto token = identifier->getSymbol();
auto name = token->getText();
if (ctx->LeftParen()) {
if (function_arity.find(name) != function_arity.end()) {
if (auto expr_list = ctx->exprList()) {
auto arity = function_arity[name];
auto arg_num = expr_list->expr().size();
if (arity != arg_num) {
errorlistener.typeError(
token->getLine(), token->getCharPositionInLine(),
"function '" + name + "' expects " + std::to_string(arity) +
" arguments, but got " + std::to_string(arg_num));
}
} else {
if (auto arity = function_arity[name]) {
errorlistener.typeError(
token->getLine(), token->getCharPositionInLine(),
"function '" + name + "' expects " + std::to_string(arity) +
" arguments, but got none");
}
}
} else {
errorlistener.typeError(token->getLine(),
token->getCharPositionInLine(),
"unknown function '" + name + "'");
}
visitChildren(ctx);
} else {
if (!inScope(name)) {
errorlistener.typeError(token->getLine(),
token->getCharPositionInLine(),
"variable '" + name + "' is not in scope");
}
}
return {};
}
visitChildren(ctx);
return {};
}
} // namespace xlang