isChar static method
Returns whether the character matches the specified conditions.
cc
is the character to test.digit
specifies if it matches digit.upper
specifies if it matches upper case.lower
specifies if it matches lower case.whitespace
specifies if it matches whitespace.match
specifies a string of characters that are matched (aka., allowed).
Implementation
static bool isChar(String cc, {bool digit = false, bool upper = false,
bool lower = false, bool whitespace = false, String? match})
=> isCharCode(cc.codeUnitAt(0), digit: digit, upper: upper,
lower: lower, whitespace: whitespace)
|| (match != null && match.contains(cc));