> 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
Actually not sure this can be done as an extension because it changes zend_operators and introduces a new handler to make it all work. > 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 So effectively it means we only call __equals if both sides are instances of the same class? > 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. Good idea. :) In brief, as it's implemented right now, the LHS takes precedence and the RHS will be called if it's the only one that implements the operation. I'll write some more tests for these cases and build that table for the RFC. > 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. If we want to guarantee symmetry by design, we have to either compare both sides or only compare if instances of the same class, or document that comparison should be implemented such that a > b == b < a, etc. I'm not convinced that a double comparison outweighs the responsibility on the user to be sensible. On Tue, 26 Jun 2018 at 21:04, Wes <netmo....@gmail.com> wrote: > 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 >
