NilCoalescingAssignmentOperators

NilCoalescingAssignmentOperators is Swift micro-library that provides two nil-coalescing/assignment-combo operators:

??=

lhs ??= rhs works like Ruby's ||= operator:

1. If lhs is non-nil, does nothing.
2. If lhs is nil but rhs is non-nil, does the assignment: lhs = rhs
3. If lhs & rhs are both nil, does nothing.

=??

lhs =?? rhs works similarly, but prefers the rhs over the lhs:

1. If rhs is nil, does nothing.
2. If rhs is non-nil, does the assignment: lhs = rhs

• If lhs & rhs are both non-nil, still does the assignment.