lib.trivial: Remove unneeded polyfills

Nix 2.3 (the minimum version needed to evaluate Nixpkgs) supports these, so no need to keep them around.
This commit is contained in:
Silvan Mosberger 2024-02-09 05:31:01 +01:00
parent 442d407992
commit 27488b861c
2 changed files with 2 additions and 56 deletions

View file

@ -95,21 +95,6 @@ in {
/* boolean and */
and = x: y: x && y;
/* bitwise and */
bitAnd = builtins.bitAnd
or (import ./zip-int-bits.nix
(a: b: if a==1 && b==1 then 1 else 0));
/* bitwise or */
bitOr = builtins.bitOr
or (import ./zip-int-bits.nix
(a: b: if a==1 || b==1 then 1 else 0));
/* bitwise xor */
bitXor = builtins.bitXor
or (import ./zip-int-bits.nix
(a: b: if a!=b then 1 else 0));
/* bitwise not */
bitNot = builtins.sub (-1);
@ -165,8 +150,8 @@ in {
inherit (builtins)
pathExists readFile isBool
isInt isFloat add sub lessThan
seq deepSeq genericClosure;
seq deepSeq genericClosure
bitAnd bitOr bitXor;
## nixpkgs version strings

View file

@ -1,39 +0,0 @@
/* Helper function to implement a fallback for the bit operators
`bitAnd`, `bitOr` and `bitXor` on older nix version.
See ./trivial.nix
*/
f: x: y:
let
# (intToBits 6) -> [ 0 1 1 ]
intToBits = x:
if x == 0 || x == -1 then
[]
else
let
headbit = if (x / 2) * 2 != x then 1 else 0; # x & 1
tailbits = if x < 0 then ((x + 1) / 2) - 1 else x / 2; # x >> 1
in
[headbit] ++ (intToBits tailbits);
# (bitsToInt [ 0 1 1 ] 0) -> 6
# (bitsToInt [ 0 1 0 ] 1) -> -6
bitsToInt = l: signum:
if l == [] then
(if signum == 0 then 0 else -1)
else
(builtins.head l) + (2 * (bitsToInt (builtins.tail l) signum));
xsignum = if x < 0 then 1 else 0;
ysignum = if y < 0 then 1 else 0;
zipListsWith' = fst: snd:
if fst==[] && snd==[] then
[]
else if fst==[] then
[(f xsignum (builtins.head snd))] ++ (zipListsWith' [] (builtins.tail snd))
else if snd==[] then
[(f (builtins.head fst) ysignum )] ++ (zipListsWith' (builtins.tail fst) [] )
else
[(f (builtins.head fst) (builtins.head snd))] ++ (zipListsWith' (builtins.tail fst) (builtins.tail snd));
in
assert (builtins.isInt x) && (builtins.isInt y);
bitsToInt (zipListsWith' (intToBits x) (intToBits y)) (f xsignum ysignum)