map() - modify an mapping, array, or string via application of a func‐
tion
mapping map( mapping | mixed* | string x, string fun, object ob,
mixed extra, ... );
mapping map( mapping | mixed* | string x, function f, mixed extra, ... );
If the first argument is a mapping, map() behaves exactly like map_map‐
ping(). If it is an array, map() behaves exactly like map_array(). If
it's argument is a string, map() passes each character (as an int) to
the function, and replaces the character with the return value if the
return value is a non-zero integer.
filter_array(3), sort_array(3), map_array(3), map_mapping(3)