diff --git a/internal/php5/parser.go b/internal/php5/parser.go
index 04a37f3..1fe5085 100644
--- a/internal/php5/parser.go
+++ b/internal/php5/parser.go
@@ -36,6 +36,10 @@ func (p *Parser) Lex(lval *yySymType) int {
 }
 
 func (p *Parser) Error(msg string) {
+	if p.errHandlerFunc == nil {
+		return
+	}
+
 	var pos = p.currentToken.Position
 	p.errHandlerFunc(errors.NewError(msg, &pos))
 }
diff --git a/internal/php7/parser.go b/internal/php7/parser.go
index e7aa50e..f9530cc 100644
--- a/internal/php7/parser.go
+++ b/internal/php7/parser.go
@@ -35,6 +35,10 @@ func (p *Parser) Lex(lval *yySymType) int {
 }
 
 func (p *Parser) Error(msg string) {
+	if p.errHandlerFunc == nil {
+		return
+	}
+	
 	var pos = p.currentToken.Position
 	p.errHandlerFunc(errors.NewError(msg, &pos))
 }