If I want to delete some elements from an Array and return itself, are foo1 and foo2 below (foo2 when there is only one element to delete) the right way to do it?
class Array
def foo1 *args; delete_if{|x| args.include?(x)} end
def foo2 arg; delete(arg); self end
end
array.reject{|element| element == value_of_element_to_be_deleted}
It's a little ugly, but the minus function does the trick concisely, subtracting one array from the other:
ary = [1, 2, 99, 3]
ary.-([99])
or
odds = [1, 3, 5, 7, 9, 99]
ary.-(odds)
The advantage here is that it is completely chainable (unlike .delete or ary - odds), so you can do things like:
ary.-(odds).average
Once your eye finds the minus sign, it's much easier to read, understand, and visually spot typos than the .delete_if construct.
It also plays well with Ruby's safe navigation operator, &., if you might get nil instead of an array. That's something you can't do elegantly with subtracting arrays.
maybe_array&.-(odds)&.average
