filter |
Discworld driver help |
filter |
Name
filter() - select certain elements
Synopsis
mixed filter( mixed x, string fun, object ob, mixed extra, ... );
mixed filter( mixed x, function f, mixed extra, ... );
Description
The (ob, fun) syntax works as if (: call_other, ob, fun :) had been passed as `f'. Filter returns a new structure containing only the elements of `x' for which the function returns nonzero. Currently, it can be used on arrays and mappings. In the case of mappings, both the key and the value are passed to the function. `extra' and all the following arguments are passed to the function after the element. For example, filter(arr, fun, 2, 3) will first call fun(x[0], 2, 3) then fun(x[1], 2, 3) etc.
