Discussion on: A simple tip for cleaner code

[Jon Bristow]

I’m fine with the quick return for validation or a guard as long as it’s right at the beginning of a function.

I’d rather have one single exit point for my function though since having multiple outs adds to the chances that someone will add code between the two exits without realizing it.

A “better” solution:

# python 2 only. Cmp was taken from the code golfers in python 3.
def silly(bar):
    output = {"-1": "NO", "0": "MAYBE", "1": "YES"}
    return output[str(cmp(bar,0))]

# LATE EDIT FOR MAXIMUM UNREADABILITY:
def silly(bar):
    return {"-1": "NO", "0": "MAYBE", "1": "YES"}[str(cmp(bar,0))]

If your function is equivalent to a nested ternary, then that’s a good use of early return. Anything more complicated needs to have the contents of the If statements extracted into methods to more clearly show off your now ternary equivalent ifelse

[JavaScript Joel]

I think OP's original example uses the conditions == 0, > 0 and < 0, so a hash table wouldn't work for 2 or -2.

[Jon Bristow]

I think if you look closer, you'll see that my solution is equivalent in output to the OP's example.

Here's a nastier one (also with a py3 equivalent)

# python2
def really_silly(bar):
    return ["MAYBE","YES","NO"][cmp(bar,0)]

# python3
def extremely_silly(bar):
    return ["MAYBE","YES","NO"][(bar>0)-(bar<0)]

God, I love how awful python can get sometimes!