Programming-Idioms

New implementation

Be concise.

Be useful.

All contributions dictatorially edited by webmasters to match personal tastes.

Please do not paste any copyright violating resource.

Please try to avoid dependencies to third-party libraries and frameworks.

Other implementations
for Item of X loop
   if P (Item) then
      Y.Append (Item);
   end if;
end loop;
(def y (filter p x))
#include <algorithm>
#include <iterator>
std::copy_if (x.begin (), x.end (), std::back_inserter(y), p);
var y = x.FindAll(p);
import std.algorithm;
auto y = [1, 2, 3, 4, 5].filter!(a => a%2==0);
import std.algorithm.iteration;
auto y = x.filter!(p);
var y = x.where(p).toList();
y = for item <- x, p.(item), do: item
y = Enum.filter(x, p)
Y = [I || I <- X, P(X)].
Y = lists:filter(P, X).
y = pack(x,mask=p(x))
y := make([]T, 0, len(x))
for _, v := range x{
	if p(v){
		y = append(y, v)
	}
}
y = filter p x
y = x.filter(p);
var y = x.stream().filter(p).collect(Collectors.toList());
val y = x.filter(p)
(setf y (remove-if-not p x))
y = {}
for _, v in ipairs(x) do
	if p(v) then y[#y+1] = v end
end
function p($element) {  /* .... */ }

$y = array_filter ($x, "p");
function Filter(vv:integer):boolean;

begin
  result :=  vv mod 2= 0;
end;

type TFilter=function(v:integer):boolean;

function FilteredArray(const x:TBoundArray;p:TFilter):TBoundArray;
var
  Idx: Integer;
  v : Integer;

begin
  setlength(result,high(x)+1);
  Idx := 0;
  for v in x do
    if p(v) then
    begin
      result[Idx] := v;
      inc(Idx);
    end;
  setlength(result,Idx);
end;
[...]
  y := FilteredArray(x,@Filter);
# You can use a subroutine as your predicate
@primes_less_than_100 = grep { is_prime($_) } 1 .. 99;

# You can also write your predicate inline
@odd_numbers = grep { $_%2 == 1 } 1 .. 99;
y = filter(p, x) 
y = [element for element in x if p(element)]
y = x.select(&:p)
let y: Vec<_> = x.iter().filter(p).collect();
val y = x.filter(p)
(define y (filter p x))