parse call expr & builtin call expr

compiler/ast/Expr.v

@@ -12,6 +12,8 @@ pub type Expr = EmptyExpr
 	| StringLiteral
 	| LoopControl
 	| ReturnExpr
+	| BuiltinCallExpr
+	| CallExpr
 	| IfExpr
 	| MatchExpr
 	| AssignExpr
@@ -84,6 +86,20 @@ pub:
 	pos  FilePos
 }
 
+pub struct BuiltinCallExpr {
+pub:
+	name string
+	args []Expr
+	pos  FilePos
+}
+
+pub struct CallExpr {
+pub:
+	left Expr
+	args []Expr
+	pos  FilePos
+}
+
 pub struct BlockExpr {
 pub:
 	stmts []Stmt

compiler/parser/expr.v

@@ -187,7 +187,27 @@ fn (mut p Parser) parse_primary_expr() ast.Expr {
 			expr = p.parse_literal()
 		}
 		.ident {
-			if p.next_tok.kind == .char {
+			if p.next_tok.kind == .bang {
+				// builtin call expr
+				mut pos := p.tok.pos
+				name := p.parse_ident()
+				p.expect(.bang)
+				p.expect(.lparen)
+				mut args := []ast.Expr{}
+				for {
+					args << p.parse_expr()
+					if !p.accept(.comma) || p.should_abort() {
+						break
+					}
+				}
+				pos += p.tok.pos
+				p.expect(.rparen)
+				expr = ast.BuiltinCallExpr{
+					name: name
+					args: args
+					pos:  pos
+				}
+			} else if p.next_tok.kind == .char {
 				if p.tok.lit == 'b' {
 					expr = p.parse_char_literal()
 				} else {
@@ -227,6 +247,24 @@ fn (mut p Parser) parse_primary_expr() ast.Expr {
 
 	for true {
 		match true {
+			p.accept(.lparen) {
+				// call expr
+				mut pos := p.prev_tok.pos
+				mut args := []ast.Expr{}
+				for {
+					args << p.parse_expr()
+					if !p.accept(.comma) || p.should_abort() {
+						break
+					}
+				}
+				pos += p.tok.pos
+				p.expect(.rparen)
+				expr = ast.CallExpr{
+					left: expr
+					args: args
+					pos:  pos
+				}
+			}
 			p.tok.kind.is_assign() {
 				op := match p.tok.kind {
 					.assign { ast.AssignOp.assign }

tests/valid/call_expr.ri

@@ -0,0 +1,12 @@
+fn main() {
+    let x = abc();
+    assert!(x == 1124);
+}
+
+fn add(a: int, b: int) int {
+    return a + b;
+}
+
+fn abc() int {
+    return add(100, 1024);
+}

tests/valid/return_expr.ri

@@ -1,5 +1,5 @@
 fn main() {
-    let x = abc;
+    let x = abc();
 }
 
 fn abc() int {