`in` (containment) operator

The non-associating, binary infix in operator is used to test whether its left-hand operand is contained in its right-hand operand.

Usage

void m(Object x, Category y) {
    Boolean contained = x in y;
}

The in operator is defined as follows:

let (x=lhs) rhs.contains(x)

Where the rhs has type Category. Since Ceylon 1.2.2 rhs with type java.util::Collection is also supported.

See the language specification for more details.

The in operator is polymorphic. The meaning of in depends on the Category interface.

The result type of the in operator is Boolean.