Currently Module#instance_methods takes a single argument, true or false, as to whether to include all ancestor's methods. However sometimes limiting the search at a particular ancestor is helpful. Currently this requires code along the lines of:
meths =  FooClass.ancestors[0..FooClass.ancestors.index(FooAncestor)].each do |anc| meths = meths | anc.instance_methods(false) end
But it would be nice if we could simply use:
This change is, practically-speaking, backward compatible, since 'true' can be the same as 'Kernel', encompassing the entire ancestry.
This change is applicable to the entire family of "methods" methods, including Kernel#methods.
This change also helps eliminate the widely disliked true|false arguments.
The particular use case that brought this to mind was trying to write a Module#conflict? method that lists the methods two modules or classes have in common, but excluding the methods that they share from a common ancestor.