Double tilde
Double tilde (~~ or ≈) may refer to: Approximation ≈ Double negation ~(~x) Smart match operator in Perl, ~~ In PostgreSQL the operator ~~ is equivalent to LIKE In certain programming languages, ~ transforms a value into an integer and takes its complement, and so ~~ (sometimes called 'two tildes' to indicate a form of double negation) is a way to transform a value into an integer.