1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
module monoid_m
use semigroup_m, only: semigroup, extended_semigroup, derive_extended_semigroup
implicit none
private
public :: monoid, extended_monoid, derive_extended_monoid
requirement monoid(T, combine, empty)
require :: semigroup(T, combine)
pure function empty()
type(T) :: empty
end function
end requirement
requirement extended_monoid(T, combine, sconcat, stimes, empty, mconcat)
require :: extended_semigroup(T, combine, sconcat, stimes)
require :: monoid(T, combine, empty)
pure function mconcat(list) result(combined)
type(T), intent(in) :: list(:)
type(T) :: combined
end function
end requirement
template derive_extended_monoid(T, combine, empty)
require :: monoid(T, combine, empty)
private
public :: stimes, mconcat
instantiate derive_extended_semigroup(T, combine), only: stimes
contains
pure function mconcat(list) result(combined)
type(T), intent(in) :: list(:)
type(T) :: combined
integer :: i
if (size(list) > 0) then
combined = list(1)
do i = 2, size(list)
combined = combine(combined, list(i))
end do
else
combined = empty()
end if
end function
end template
end module
|
