[Nix-dev] Convert sha1 from base64 into "normal" string

[Игорь Пашев]

Hi all.

What options are there to convert a base64-encoded raw binary data
into "normal" hexadecimal string in Nix (during evalutation)?

E. i. "kjOzmCPxyw0bPciMsGSh5q+bT9g=" ->
"9233b39823f1cb0d1b3dc88cb064a1e6af9b4fd8"

to make it valid input for fetchurl, etc.