Find the first forbidden char in an identifier, if any
Valid identifier are solely composed of [a-z][A-Z][0-9][._-] If any char isn't in that list, this function returns its index.
String to validate
The index at which the invalid char is, or str.length if there isn't any
See Implementation
Find the first forbidden char in an identifier, if any
Valid identifier are solely composed of [a-z][A-Z][0-9][._-] If any char isn't in that list, this function returns its index.