Add comparison operators

Signed-off-by: CHatingPython <chatingpython@gmail.com>

furc/src/ast.cpp

@@ -82,6 +82,12 @@ std::ostream& operator<<(std::ostream& os, binop_expression_node_t type) {
     case binop_expression_node_t::Mul: return os << '*';
     case binop_expression_node_t::Div: return os << '/';
     case binop_expression_node_t::Mod: return os << '%';
+    case binop_expression_node_t::Equal: return os << "==";
+    case binop_expression_node_t::NotEqual: return os << "!=";
+    case binop_expression_node_t::LessThan: return os << '<';
+    case binop_expression_node_t::GreaterThan: return os << '>';
+    case binop_expression_node_t::LessEqual: return os << "<=";
+    case binop_expression_node_t::GreaterEqual: return os << ">=";
     }
 }
 
@@ -96,7 +102,7 @@ bool binop_expression_node::equal(const node& rhsNode) const {
 }
 
 std::ostream& var_assign_expression_node::print(std::ostream& os) const {
-    return os << *m_lhs << " = " << *m_rhs;
+    return os << '(' << *m_lhs << ' ' << m_compound << "= " << *m_rhs << ')';
 }
 
 bool var_assign_expression_node::equal(const node& rhsNode) const {

furc/src/front/lexer.cpp

@@ -127,6 +127,12 @@ token_handle<> lexer::next_token() {
             { "*=", token_t::StarEq },
             { "/=", token_t::SlashEq },
             { "%=", token_t::PercentEq },
+            { "==", token_t::DEq },
+            { "!=", token_t::NotEq },
+            { "<", token_t::LessThan },
+            { ">", token_t::GreaterThan },
+            { "<=", token_t::LessEq },
+            { ">=", token_t::GreaterEq },
         };
 
         token_t     type   = token_t::None;

furc/src/front/parser.cpp

@@ -271,6 +271,12 @@ ast::expression_node_h parser::parse_expression_rhs(ast::expression_node_h&& ini
         { token_t::StarEq, rhsop_info::create(ast::binop_expression_node_t::Mul) },
         { token_t::SlashEq, rhsop_info::create(ast::binop_expression_node_t::Div) },
         { token_t::PercentEq, rhsop_info::create(ast::binop_expression_node_t::Mod) },
+        { token_t::DEq, rhsop_info::create(ast::binop_expression_node_t::Equal, 10, associativity::Left) },
+        { token_t::NotEq, rhsop_info::create(ast::binop_expression_node_t::NotEqual, 10, associativity::Left) },
+        { token_t::LessThan, rhsop_info::create(ast::binop_expression_node_t::LessThan, 9, associativity::Left) },
+        { token_t::GreaterThan, rhsop_info::create(ast::binop_expression_node_t::GreaterThan, 9, associativity::Left) },
+        { token_t::LessEq, rhsop_info::create(ast::binop_expression_node_t::LessEqual, 9, associativity::Left) },
+        { token_t::GreaterEq, rhsop_info::create(ast::binop_expression_node_t::GreaterEqual, 9, associativity::Left) },
     };
 
     ast::expression_node_h lhs = std::move(init);

furc/src/main.cpp

@@ -5,7 +5,7 @@
 #include <iostream>
 
 int main(void) {
-    furc::front::parser parser("<TEMP>", "func main() {\n    return (x - -y) * z++;\n}");
+    furc::front::parser parser("<TEMP>", "func main() {\n    return x = y;\n}");
     std::cout << parser.parse() << '\n';
 
     return 0;