.\"return a selective sub-array
.TH filter_array 3

.SH NAME
filter_array() - return a selective sub-array

.SH SYNOPSIS
mixed *filter_array( mixed *arr, string fun, object ob, mixed extra );

.SH DESCRIPTION
filter_array() returns an array holding the items of <arr> which
passed sucessfully through the function <fun> found in object <ob>.
The function <fun> is called for each element in <arr> with that
element as parameter.  The second parameter <extra> is sent in each
call if given.  An object is considered to have passed sucessfully
through <fun> (and hence is included in the return array) if <fun>
returns 1.
If <arr> is not an array, then 0 will be returned.