Add ensure(Eachable1, Present)

[antonio-pedro99]

Hi @ilyash-b, could you provide more info on this?

[ilyash-b]

Hi @antonio-pedro99!

In general, ensure(original, pattern) returns a value which would match the pattern. The operation to make the original conform to the pattern should be minimal and obvious.

my_arr = [1,2,3]
my_arr =~ Has(1)  # true
my_arr =~ Has(4)  # false
ensure(my_arr, Has(4))  # [1,2,3,4]

[antonio-pedro99]

I did not understand this

ensure(my_arr, Has(4))

Returning 1, 2, 3 + the element that is not present.

[ilyash-b]

Not sure I understand your comment. I'll try to explain slightly different and see if it works.

ensure(x, pattern) should return a value that would match the pattern. In other words, ensure(x, pattern) =~ pattern should succeed.

• If x =~ pattern when ensure() is called, it just needs to return x
• Otherwise, ensure() should minimally transform (a copy of) x so that returned value matches the pattern

In the example of ensure(my_arr, Has(4)), where 4 is not in my_arr that minimal transformation would be to return a new value with all the elements of my_arr with the item 4 appended.

[ilyash-b]

In dev