Hidden Inversions (Cops' Thread) This is a cops-and-robbers puzzle the robbers' thread can be found here.
Your task will be two write two programs (or functions) such that they are anagrams of each other and one performs the left inverse of the other.  These programs may accept and output as many integers or complex numbers as you wish.  If you choose take numbers as character points or any other reasonable means you must indicate you are doing so in your answer.  If you choose to restrict the domain of your function you must also indicate the restricted domain in your answer.
You will then present the first program in the form of an answer with left inverse hidden for robbers to find.
The shown program must implement a injective function (otherwise it would be impossible for a hidden answer to exist).
If your answer has not been cracked in one week you may reveal the hidden answer and mark it as safe.  Safe answers cannot be cracked by robbers and will remain un-cracked indefinitely.
The goal will be to create the shortest un-cracked answer in bytes.
Example
You could show the following python program that adds one to the input
lambda x:~-x

A solution could be:
lambda x:-~x

This subtracts one from the input
Python 3, 80 bytes (Cracked)

bhmq = int(input())
print(bhmq ** 2)
(1 or [(sqrt),(specification+of*integerr)])


Domain: positive integers. Function is just squaring of a number. Input to stdin, output to stdout, as well as in the inverse function. Note that Python ignores the third line here, because it is syntactically valid and 1 is already a truthy value, so Python doesn't even look whether the right part of 'or' is well-defined.

Robbers should write a sqrt function that will work correct on all non-zero squares, printing integer value as is, without floating point (so on input '4' output should be '2' or '2\n', not '2.0' or '2.0\n').