implement MethodExpr

Author: itchyny

ast/node.go

@@ -427,6 +427,16 @@ type SliceExpr struct {
 
 func (f *SliceExpr) Pos() Pos { return f.Lbrack }
 
+// vimlparser: METHOD .left .right
+type MethodExpr struct {
+	Left   Expr   // this object
+	Method Expr   // method
+	Lparen Pos    // position of "("
+	Args   []Expr // function arguments; or nil
+}
+
+func (c *MethodExpr) Pos() Pos { return c.Lparen }
+
 // vimlparser: CALL .left .rlist
 type CallExpr struct {
 	Fun    Expr   // function expression
@@ -588,6 +598,7 @@ func (*BinaryExpr) exprNode()    {}
 func (*UnaryExpr) exprNode()     {}
 func (*SubscriptExpr) exprNode() {}
 func (*SliceExpr) exprNode()     {}
+func (*MethodExpr) exprNode()    {}
 func (*CallExpr) exprNode()      {}
 func (*DotExpr) exprNode()       {}
 func (*BasicLit) exprNode()      {}

ast/walk.go

@@ -164,6 +164,11 @@ func Walk(v Visitor, node Node) {
 		Walk(v, n.Low)
 		Walk(v, n.High)
 
+	case *MethodExpr:
+		Walk(v, n.Left)
+		Walk(v, n.Method)
+		walkExprList(v, n.Args)
+
 	case *CallExpr:
 		Walk(v, n.Fun)
 		walkExprList(v, n.Args)

compiler/compiler.go

@@ -387,6 +387,14 @@ func (c *Compiler) compileExpr(node ast.Expr) string {
 			h = c.compileExpr(n.High)
 		}
 		return fmt.Sprintf("(slice %s %s %s)", x, l, h)
+	case *ast.MethodExpr:
+		name := c.compileExpr(n.Left)
+		args := make([]string, 0, len(n.Args)+1)
+		args = append(args, c.compileExpr(n.Method))
+		for _, a := range n.Args {
+			args = append(args, c.compileExpr(a))
+		}
+		return fmt.Sprintf("(method %s (%s))", name, strings.Join(args, " "))
 	case *ast.CallExpr:
 		name := c.compileExpr(n.Fun)
 		if len(n.Args) > 0 {

go/export.go

@@ -343,6 +343,14 @@ func newAstNode(n *VimNode, filename string) ast.Node {
 			High:   newExprNode(n.rlist[1], filename),
 		}
 
+	case NODE_METHOD:
+		return &ast.MethodExpr{
+			Lparen: pos,
+			Left:   newExprNode(n.left, filename),
+			Method: newExprNode(n.right.left, filename),
+			Args:   newRlist(*n.right, filename),
+		}
+
 	case NODE_CALL:
 		return &ast.CallExpr{
 			Lparen: pos,