- alnum IsAlnum Alphanumeric
- alpha IsAlpha Alphabetic
- ascii IsASCII Any ASCII char
- blank IsSpace [ \t] Horizontal whitespace (GNU)
- cntrl IsCntrl Control characters
- digit IsDigit \d Digits
- graph IsGraph Alphanumeric and punctuation
- lower IsLower Lowercase chars (locale aware)
- print IsPrint Alphanumeric, punct, and space
- punct IsPunct Punctuation
- space IsSpace [\s\ck] Whitespace
- IsSpacePerl \s Perl's whitespace definition
- upper IsUpper Uppercase chars (locale aware)
- word IsWord \w Alphanumeric plus _ (Perl)
- xdigit IsXDigit [\dA-Fa-f] Hexadecimal digit
+ alnum IsAlnum Alphanumeric
+ alpha IsAlpha Alphabetic
+ ascii IsASCII Any ASCII char
+ blank IsSpace [ \t] Horizontal whitespace (GNU extension)
+ cntrl IsCntrl Control characters
+ digit IsDigit \d Digits
+ graph IsGraph Alphanumeric and punctuation
+ lower IsLower Lowercase chars (locale and Unicode aware)
+ print IsPrint Alphanumeric, punct, and space
+ punct IsPunct Punctuation
+ space IsSpace [\s\ck] Whitespace
+ IsSpacePerl \s Perl's whitespace definition
+ upper IsUpper Uppercase chars (locale and Unicode aware)
+ word IsWord \w Alphanumeric plus _ (Perl extension)
+ xdigit IsXDigit [0-9A-Fa-f] Hexadecimal digit