How to fold text between two regular expressions ?

[MM]

How do I create folds such that it starts at matched expression and
ends at the line containing  part of the matched expression.
e.g i'd like to fold

procedure xyz ( .....
:
:
:
:
:
end xyz;

function abc (
:
:
:
:
:
end abc;

impure function pqr (
:
:
:
:
:
end pqr;

Thanks in advance..