blob: 882005dc1b5c64b7eefd7ae422fded8b80f2491c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
with builtins;
rec {
fold = op: nul: list:
if list == []
then nul
else op (head list) (fold op nul (tail list));
concat =
fold (x: y: x + y) "";
and = fold (x: y: x && y) true;
flatten = x:
if isList x
then fold (x: y: (flatten x) ++ y) [] x
else [x];
sum = fold (x: y: add x y) 0;
hasSuffix = ext: fileName:
let lenFileName = stringLength fileName;
lenExt = stringLength ext;
in !(lessThan lenFileName lenExt) &&
substring (sub lenFileName lenExt) lenFileName fileName == ext;
# Split a list at the given position.
splitAt = pos: list:
if pos == 0 then {first = []; second = list;} else
if list == [] then {first = []; second = [];} else
let res = splitAt (sub pos 1) (tail list);
in {first = [(head list)] ++ res.first; second = res.second;};
# Stable merge sort.
sortBy = comp: list:
if lessThan 1 (length list)
then
let
split = splitAt (div (length list) 2) list;
first = sortBy comp split.first;
second = sortBy comp split.second;
in mergeLists comp first second
else list;
mergeLists = comp: list1: list2:
if list1 == [] then list2 else
if list2 == [] then list1 else
if comp (head list2) (head list1) then [(head list2)] ++ mergeLists comp list1 (tail list2) else
[(head list1)] ++ mergeLists comp (tail list1) list2;
id = x: x;
const = x: y: x;
range = first: last:
if builtins.lessThan last first
then []
else [first] ++ range (builtins.add first 1) last;
}
|
