Retrieve

The function described here restores an element of a coproduct to its original state.

Retrieve(x) : CopElt -> Elt
Given an element x of some coproduct C, return the element as an element of the structure that formed its parent before it was mapped into C.

Example Cop_cop (H15E1)

We illustrate basic uses of the coproduct constructors and functions. 
> C := cop<IntegerRing(), Strings()>;
> x := C ! 5;
> y := C ! "abc";
> x;
5
> y;
abc
> Parent(x);
Coproduct<Integer Ring, String structure>
> x eq 5;
true
> x eq y;
false
> Retrieve(x);
5
> Parent(Retrieve(x));
Integer Ring
V2.28, 13 July 2023