Workflow Composition

Request Score Workflow

Call and Combine

A workflow can call an internal function, return a derived value, and combine it with local state.

Program

Play the program to choose a request count and watch the call contribute to the final score.

request_score_workflow.f90 
program request_score_workflow_demo
    implicit none
    integer :: request_count
    integer :: base_points
    integer :: bonus_points
    integer :: total_points

    request_count = 
    base_points = 10
    bonus_points = score_bonus(request_count)
    total_points = base_points + bonus_points
    print '(I0, 1X, I0)', request_count, total_points

contains
    function score_bonus(count) result(points)
        integer, intent(in) :: count
        integer :: points
        points = count * 3
    end function score_bonus
end program request_score_workflow_demo

program request_score_workflow_demo
    implicit none
    integer :: request_count
    integer :: base_points
    integer :: bonus_points
    integer :: total_points

    request_count = 
    base_points = 10
    bonus_points = score_bonus(request_count)
    total_points = base_points + bonus_points
    print '(I0, 1X, I0)', request_count, total_points

contains
    function score_bonus(count) result(points)
        integer, intent(in) :: count
        integer :: points
        points = count * 3
    end function score_bonus
end program request_score_workflow_demo

program request_score_workflow_demo
    implicit none
    integer :: request_count
    integer :: base_points
    integer :: bonus_points
    integer :: total_points

    request_count = 
    base_points = 10
    bonus_points = score_bonus(request_count)
    total_points = base_points + bonus_points
    print '(I0, 1X, I0)', request_count, total_points

contains
    function score_bonus(count) result(points)
        integer, intent(in) :: count
        integer :: points
        points = count * 3
    end function score_bonus
end program request_score_workflow_demo
internal function `contains` lets the program define a local function used by the main workflow.
call step `score_bonus(request_count)` jumps to the function and returns a value.
composition The final total combines local state with the function result.