OpenEuphoria

Re: Help needed with walk_dir()

• Posted by mattlewis (admin) Aug 04, 2010
• 1027 views

It's a pointer in that it "points to" your routine. It does not refer to a particular place in memory (which is what is commonly meant when someone talks about a pointer). Effectively, you could think of it where the back end maintains a list of the routines, and the routine id is the index into that list. It's basically equivalent to:

 
procedure foo() 
    -- ...do stuff 
end procedure 
 
procedure bar() 
    -- ...do stuff 
end procedure 
 
procedure baz() 
    -- ...do stuff 
end procedure 
 
sequence ROUTINES = {"foo", "bar", "baz"} 
 
function my_routine_id( sequence name ) 
    return find( name, ROUTINES ) 
end function 
 
procedure my_call_proc( integer id ) 
    if id = 1 then 
        foo() 
    elsif id = 2 then 
        bar() 
    elseif id = 3 then 
        baz() 
    else 
        -- crash, bad routine id! 
    end if 
end procedure 
 
integer foo_id 
foo_id = my_routine_id("foo") 
 
my_call_proc( foo_id ) 
 

You can also get a better feel by looking at the euphoria based back end. It's still pretty dense, and not terribly easy to jump right into, but there is an implementation of routine id built in pure euphoria in there.

Matt