fix scanner and update regexes

src/grammar.json

@@ -138,11 +138,11 @@
     },
     "number": {
       "type": "PATTERN",
-      "value": "-?(?:[0-9]+(?:\\.[0-9]*)?|\\.[0-9]+)(?:[eE]-?[0-9]+)?"
+      "value": "[-+]?(?:[0-9]+(?:\\.[0-9]*)?|\\.[0-9]+)(?:[eE][0-9]+)?"
     },
     "string": {
       "type": "PATTERN",
-      "value": "\"(?:[^\"\\\\]|\\\\\\\\|\\\\\")*\"|'(?:[^'\\\\]|\\\\\\\\|\\\\')*'"
+      "value": "\"(?:[^\"\\\\]|\\\\[^\\n])*\"|'(?:[^'\\\\]|\\\\[^\\n])*'"
     },
     "attribute": {
       "type": "PATTERN",