Oleg Broytman wrote:
On Wed, Apr 04, 2012 at 12:52:00PM -0700, Ethan Furman wrote:
Forced? I do not use Python to be forced to use one style of programming over another.
Then it's strange you are using Python with its strict syntax (case-sensitivity, forced indents), ubiquitous exceptions, limited syntax of lambdas and absence of code blocks (read - forced functions), etc.
I come from assembly -- 'a' and 'A' are *not* the same. indents -- I already used them; finding a language that gave them the same importance I did was incredible. exceptions -- Python uses them, true, but I don't have to in my own code (I do, but that's besides the point). lambdas -- they work just fine for my needs. etc.
And it's not like returning None will allow some clock calls to work but not others -- as soon as they try to use it, it will raise an exception.
There is a philosophical distinction between EAFP and LBYL. I am mostly proponent of LBYL. Well, I am partially retreat. "Errors should never pass silently. Unless explicitly silenced." get_clock(FLAG, on_error=None) could return None.
It's only an error if it's documented that way and, more importantly, thought of that way. The re module is a good example: if it can't find what you're looking for it returns None -- it does *not* raise a NotFound exception. I see get_clock() the same way: I need a clock that does xyz... None? Okay, there isn't one. ~Ethan~