The "not" operator reverses a condition, making it true if it had been false, and false if it had been true. You can create these conditions with the relational operators =, ≠, >, ≥, <, and ≤, with functions such as isPrime(), pxlTest(), and ptTest(), or with any other expression that returns 'true' or 'false'. Other operators for dealing with conditions are and, or, and xor.
In output, it can also appear as ~, and if you type the ~ character, it will be interpreted as "not".
:not 2+2=4 false :not x ~x
The operator can also be applied to an integer, treating it as a 32-bit signed integer (larger integers will be truncated to fit) expressed in binary. In this case, it gives the 1's complement, flipping all the bits.
:(not 0b1111)▶Bin 0b11111111111111111111111111110000 :not 1000 -1001
60 - Argument must be a Boolean expression or integer happens when the data type is incorrect.