{ lib, ... }: with lib; rec { escape = let isSafeChar = testString "[-+./0-9:=A-Z_a-z]"; in x: if x == "" then "''" else stringAsChars (c: if isSafeChar c then c else if c == "\n" then "'\n'" else "\\${c}" ) x; # # shell script generators # # example: "${cat (toJSON { foo = "bar"; })} | jq -r .foo" cat = s: "printf '%s' ${escape s}"; }