Merge pull request #6 from sonda2208/correct-names-in-ast

Correct some struct names

ast.go

@@ -12,15 +12,15 @@ type Expr interface {
 	Type() string
 }
 
-type ExprExpr struct {
+type ParentExpr struct {
 	Expr Expr
 }
 
-func (e *ExprExpr) String() string {
+func (e *ParentExpr) String() string {
 	return fmt.Sprintf("(%s)", e.Expr.String())
 }
 
-func (e *ExprExpr) Type() string {
+func (e *ParentExpr) Type() string {
 	return "nested expression"
 }
 
@@ -38,15 +38,15 @@ func (e *BinaryExpr) Type() string {
 	return "binary expression"
 }
 
-type Var struct {
+type Ident struct {
 	Val string
 }
 
-func (v *Var) String() string {
+func (v *Ident) String() string {
 	return v.Val
 }
 
-func (v *Var) Type() string {
+func (v *Ident) Type() string {
 	return "variable"
 }
 
@@ -153,7 +153,7 @@ func walk(expr Expr, fn WalkFunc) error {
 		if err != nil {
 			return err
 		}
-	case *ExprExpr:
+	case *ParentExpr:
 		err = walk(e.Expr, fn)
 		if err != nil {
 			return err

evaluator.go

@@ -30,7 +30,7 @@ func evaluate(expr Expr, params map[string]interface{}) (Expr, error) {
 	}
 
 	switch e := expr.(type) {
-	case *ExprExpr:
+	case *ParentExpr:
 		return evaluate(e.Expr, params)
 	case *BinaryExpr:
 		l, err := evaluate(e.LHS, params)
@@ -44,7 +44,7 @@ func evaluate(expr Expr, params map[string]interface{}) (Expr, error) {
 		}
 
 		return compute(e.Op, l, r)
-	case *Var:
+	case *Ident:
 		varName := e.Val
 		varVal, ok := params[varName]
 		if !ok {

parser.go

@@ -89,7 +89,7 @@ func parseExpr(rule *Rule) (Expr, error) {
 			}
 		}
 
-		return &ExprExpr{Expr: res}, nil
+		return &ParentExpr{Expr: res}, nil
 	}
 
 	l, err := toLiteral(rule.Val)
@@ -99,7 +99,7 @@ func parseExpr(rule *Rule) (Expr, error) {
 
 	return &BinaryExpr{
 		Op:  rule.Op,
-		LHS: &Var{rule.Var},
+		LHS: &Ident{rule.Var},
 		RHS: l,
 	}, nil
 }