what’s the easiest way to format a hex number with fixed width and leading zeros? example: number 7 width 4 -> 0007

@andreiformiga how about bytes->hex-string?

If you have a number and you want a string, maybe use integer->integer-bytes first.

racket@> (require file/sha1)
racket@> (bytes->hex-string (integer->integer-bytes #x000f 2 #f #t))
"000f"

@dedbox I didn’t know about bytes->hex-string, thanks (though I’m not sure about having to import the whole module just for this function)

Then import just that function (require (only-in file/sha1 bytes->hex-string))