type cast

parser.v

@@ -70,7 +70,7 @@ fn (mut s SymbolTable) is_in_global_scope() bool {
 
 // ------------------------------------------- Expressions
 
-type Expr = VoidExpr | BinaryExpr | IntegerLiteral | RealLiteral | BoolLiteral | Variable | TypeExpr | Function
+type Expr = VoidExpr | BinaryExpr | IntegerLiteral | RealLiteral | BoolLiteral | Variable | TypeExpr | Function | TypeCast
 type LiteralExpr = IntegerLiteral | RealLiteral | BoolLiteral
 
 struct VoidExpr {}
@@ -105,6 +105,11 @@ struct Function {
 	name string
 }
 
+struct TypeCast {
+	expr Expr
+	type string
+}
+
 // ------------------------------------------- Statements
 
 type Stmt = VarDecl | ExprStmt | ReturnStmt | Block | FuncDecl
@@ -194,8 +199,8 @@ fn (mut p Parser) parse_primary() Expr {
 		.real       {RealLiteral{token.text.f32()}}
 		.boolean    {BoolLiteral{token.text == 'true'}}
 		.identifier {Variable{token.text}}
-		.type       {TypeExpr{token.text}}
 		.kw_fn      {Function{token.text}}
+		.type       {p.parse_type(token.text)}
 		else {parse_error("Unexpected Token")}
 	}
 }
@@ -216,7 +221,27 @@ fn (mut p Parser) parse_expr() Expr {
 fn (mut p Parser) parse_binary(left Expr, op string) BinaryExpr {
 	p.next()
 	right := p.parse_expr()
-	return BinaryExpr{left, op, right}
+	binary_expr := BinaryExpr{left, op, right}
+	if !p.is_op_valid_for_type(p.get_expr_type(binary_expr), op) {
+		parse_error("Illegal operation ${op} for type ${p.get_expr_type(binary_expr)}")
+	}
+	return binary_expr
+}
+
+fn (mut p Parser) parse_type(type string) Expr {
+
+	if p.peek().type == .lparen {
+		p.next()
+		expr := p.parse_expr()
+		p.expect(.rparen)
+
+		return TypeCast {
+			expr: expr
+			type: type
+		}
+	}
+
+	return TypeExpr {name: type}
 }
 
 fn (mut p Parser) get_expr_type(expr Expr) string {
@@ -240,8 +265,21 @@ fn (mut p Parser) get_expr_type(expr Expr) string {
 			}
 			return info.type
 		}
+		TypeCast {expr.type}
 		else {"Tried getting type of unexpected Expr"}
 	}
+
+
+}
+
+fn (mut p Parser) is_op_valid_for_type(type string, op string) bool {
+	legal_ops := match type {
+		'int' {['+', '-', '*', '/', '<', '>', '=']}
+		'real' {['+', '-', '*', '/', '<', '>', '=']}
+		'bool' {['=']}
+		else {[]}
+	}
+	return op in legal_ops
 }
 
 // ------------------------------------------- Statements
@@ -269,6 +307,8 @@ fn (mut p Parser) parse_statement() Stmt {
 		}
 }
 
+
+
 fn (mut p Parser) parse_var_decl() VarDecl {
 	p.expect(.kw_let)
 
@@ -350,7 +390,6 @@ fn (mut p Parser) parse_return_stmt() ReturnStmt {
 	p.expect(.kw_return)
 
 	token := p.peek()
-	p.dump_token()
 	mut expr := Expr{}
 	expr = match token.type {
 		.integer    {IntegerLiteral{token.text.int()}}
@@ -378,6 +417,7 @@ fn (mut p Parser) parse_expr_stmt() ExprStmt {
 	}
 }
 
+
 fn (mut p Parser) parse_block(no_scope bool) Block {
 	p.expect(.lbracket)
 

test.one

@@ -1,9 +1,2 @@
-fn foo() int {
+let a real = 5.1;
-  let y int = 2;
+let x real = 7.0 + real(int(a) + int(7.0));
-  let z int = y*2;
-  return y;
-}
-
-fn bar() real {
-  return 5.5;
-}