[EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
> def add(x, y):
> if x == 0:
> print y
> return y
> else:
> x -= 1
> y += 1
> add(x, y)
To add to the other good advice in this thread:
This is just one of many reasons why I advocate always having a
*single* return statement, at the *end* of the function. I usually
start out writing my function setting a default return value, and the
return statement immediately below.
In your case, the default return value is None, so let's make that
explicit.
def recursive_add(x, y):
result = None
return result
Then, the rest of the function's responsibility is about changing that
default value if necessary.
def recursive_add(x, y):
result = None
if x == 0:
print y
result = y
else:
x -= 1
y += 1
recursive_add(x, y)
return result
With this structure, it becomes quickly obvious what's gone wrong: one
of the branches is not changing the default return value.
def recursive_add(x, y):
if x == 0:
print y
result = y
else:
x -= 1
y += 1
result = recursive_add(x, y)
return result
I find this much less error-prone than hiding return statements in
branches throughout the function; if the only return statement is at
the very end of the function, it becomes much easier to read.
--
\ "If you go to a costume party at your boss's house, wouldn't |
`\ you think a good costume would be to dress up like the boss's |
_o__) wife? Trust me, it's not." -- Jack Handey |
Ben Finney
--
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