programming logical functions: myand, myor and mynot

[Gernot]

"Eddie Corns" <eddie at holyrood.ed.ac.uk> schrieb im Newsbeitrag
news:9t3p3q$rvl$1 at scotsman.ed.ac.uk...
> "Gernot" <headroom02 at gmx.de> writes:
>
[deleted]
>
> I think you've correctly worked out that AND is equivalent to the nested
if
> statements but it's not clear from the example what you're trying to do.
> If you are in fact trying to evaluate input from the user you need to
choose a
> representation for true and false (such as 't' and 'f') and make explicit
> tests for these.
> If the input is just for testing and you're trying to understand how myand
> works, then you just need to think of 'x' and 'y' as _expressions_, which
will
> be evaluated to true or false in the right context (I can't think of
another
> way of saying this as a hint rather than giving the answer outright).

That´s right, but I did not have the idea on my own, some students opened my
eyes, they gave me this program (it is done with your idea):

#######################
def truth ():
    return "oneword" != "anotherword"

def antitruth ():
    return "oneword" == "anotherword"

def myand (a,b):
    if (a == truth()):
        if (b == truth()):
            return truth()
        else:
            return antitruth()
    else:
        return antitruth()

def myor (a,b):
    if (a == truth()):
        return truth()
    else:
        if (b == truth()):
            return truth()
        else:
            return antitruth()

def mynot (a):
    if (a == truth()):
        return antitruth()
    else:
        return truth()

def usethistoprint (a):
    if (a == truth()):
        print "True"
    else:
        print "False"
##########################

I think, that is pretty implementation, I hope I will be able to do this on
my own, soon.

Thank you for your comment.

Gernot