Funny Firebird operators

Here is a table with Firebird operators you probably don’t know that exist:

Funny Standard equivalent
x !< y not (x < y)
x ^< y not (x < y)
x ~< y not (x < y)
x !> y not (x > y)
x ^> y not (x > y)
x ~> y not (x > y)
x != y x <> y
x ^= y x <> y
x ~= y x <> y