@char_is_alnum(string)
@char_is_alpha(string)
@char_is_ascii(string)
@char_is_blank(string)
@char_is_cntrl(string)
@char_is_digit(string)
@char_is_graph(string)
@char_is_lower(string)
@char_is_print(string)
@char_is_punct(string)
@char_is_space(string)
@char_is_upper(string)
@char_is_xdigit(string)

The predicates @char_is_xxx(s) returns true if all characters in s are in the class xxx. These classes are defined as follows:

• alnum Any alphanumeric character
• alpha Any alphabetic character
• ascii Anay character between 0 and octal 0177 inclusive.
• blank Any whitespace character that is not a line separator
• cntrl Any control character
• digit Any decimal digit
• graph Any graphical character
• lower Any lowercase character
• print Any printable character
• punct Any punctuation character
• space Any whitespace character
• upper Any uppercase character
• xdigit Any hexadecimal digit character

See also String Management @car,    @cdr,    @char_is_alnum,    @char_is_alpha,    @char_is_ascii,    @char_is_blank,    @char_is_cntrl,    @char_is_digit,    @char_is_graph,    @char_is_lower,    @char_is_print,    @char_is_punct,    @char_is_space,    @char_is_upper,    @char_is_xdigit,    @copy,    @count,    @drop,    @dump,    @dumpvar,    @empty,    @explode,    @find,    @is_prefix,    @is_string,    @is_subsequence,    @is_suffix,    @last,    @member,    @occurs,    @parse,    @permute,    @push_back,    @r_compile,    @r_findall,    @r_match,    @r_search,    @remove,    @remove_duplicate,    @replace,    @scramble,    @slice,    @sort,    @sputter,    @string2fun,    @strip_path,    @stutter,    @string2proc,    @system,    @take    @to_num,    @Tracing,    @UnTracing