use the is_NUM_START helper

Author: ichiriac

src/lexer/property.js

@@ -54,7 +54,7 @@ module.exports = {
   },
   matchST_VAR_OFFSET: function() {
     const ch = this.input();
-    if (this.is_NUM()) {
+    if (this.is_NUM_START()) {
       this.consume_NUM();
       return this.tok.T_NUM_STRING;
     } else if (ch === "]") {

src/lexer/scripting.js

@@ -69,13 +69,13 @@ module.exports = {
       default:
         if (ch === ".") {
           ch = this.input();
-          if (this.is_NUM()) {
+          if (this.is_NUM_START()) {
             return this.consume_NUM();
           } else {
             if (ch) this.unput(1);
           }
         }
-        if (this.is_NUM()) {
+        if (this.is_NUM_START()) {
           return this.consume_NUM();
         } else if (this.is_LABEL_START()) {
           return this.consume_LABEL().T_STRING();