
addBit
>>>>
What exactly is the definition of recursion? Is it simply being caught in an
infinite repeat loop
<<<<
I don't think so.
>>>>
Is it, from the standpoint of logic, necessarily tautological
<<<<
not really
In short, I'm wondering what the relations between recursion, repetition,
redundancy, truth, and selfreference are. A ponderous matter, I know, but
I'd be curious to know if any of you have thoughts on it.
keith seward
<<<<
Keith,
I'm self taught myself but as I understood recursions the clou of it is to
design a function in a way that is does just one "repeat" of a variable/unknown
amount of "repeats" and then let it decide via the conditional whether it is
done or it should call itself once again.
On a simple example, very basic in assembler but not so in lingo: add 1 to a
byte of n bit. If n = 3 the sequence of results could look like this:
[0, 0, 0]
[1, 0, 0]
[0, 1, 0]
[1, 1, 0]
[0, 0, 1]
[1, 0, 1]
[0, 1, 1]
[1, 1, 1]
The logic is simple:
If the digit to the left is 0 then make it 1, done.
If it is 1 then make it 0, go to the next digit and (do the same with the next
digit)
I think there are other solutions to this based on repeat loops but when I
encountered a problem which needed an addBit function I found it the most
logical and easiest way to make the function call itself until done.
on addBit LBits,digit
 lsb is on the left here
if voidP(digit) then set digit = 1
 some ritual error checking first
if not listP(LBits) or digit < 1 then return "bad input"
set Bit.Cnt = Count(LBits)
if digit > Bit.Cnt then return
 the fun starts here
set test = getat(LBits,Digit)
if not test then
setat LBits,digit,TRUE
else
setat LBits,digit,FALSE
set Digit=Digit + 1
if Digit <= Bit.Cnt then
addBit(LBits,Digit)
end if
end if
 this line is unnecessary since we deal with a list
 however, added for convenience of MessWin testing
return LBits
end
