some ideas and concerns: - I would like to see this in an extension first, i think it's perfectly doable and people can test it before merging to core
- would be nice if compareTo and equals were used only if left operand and right operand used the same comparator function. In other words, $a == $b must not work if $a->__equals and $b->__equals are two different functions - otherwise RFC should specify the precedence. if $left operand and $right operand both have the magic methods, it will call $left->__magic($right), otherwise, if only the right one has the handler? what if the right one has compareTo and the left has only equal? you probably should add a table that explains which method is called depending in the availability of the two magic methods in the operands. - I'd introduce a debug mode that forces php to call both $left->__equals($right) and $right->__equals($left) so that symmetry is guaranteed by design. You could do that when "assertions" are active. gl
