|| config.languageMode == LanguageMode.ECMASCRIPT6_STRICT;
}
double normalizeNumber(LiteralToken token) {
String value = token.value;
SourceRange location = token.location;
int length = value.length();
Preconditions.checkState(length > 0);
Preconditions.checkState(value.charAt(0) != '-'
&& value.charAt(0) != '+');
if (value.charAt(0) == '.') {