Documentation, assignment in expression.

Tim Chase python.list at
Sun Mar 25 15:48:31 CEST 2012

On 03/25/12 08:11, Chris Angelico wrote:
> On Mon, Mar 26, 2012 at 12:03 AM, Tim Chase
> <python.list at>  wrote:
>> Granted, this can be turned into an iterator with a yield, making the issue
>> somewhat moot:
> No, just moving the issue to the iterator. Your iterator has exactly
> the same structure in it.

Yeah, it has the same structure internally, but I'm somewhat 
surprised that the DB connection object doesn't have an 
__iter__() that does something like this automatically under the 

> Personally, I quite like assignment-in-conditional notation. Yes, it's
> a pretty common cause of problems; but what happened to the
> "consenting adults" policy? Python permits operator overloading and
> even the reassignment of builtins, both of which can cause similar
> confusion.

In my past years of C programming, I've accidentally omitted the 
second "=" in a comparison test numerous times, requiring me to 
track down the missing character.  When I finally catch it, it's 
obvious what the problem is, but I've come to love having Python 
yell at me contextually.

> But, that's the choice Python's made. And being able to use the same
> symbol for assignment and comparison does have its advantages.

The old curmudgeon in me likes the Pascal method of using "=" for 
equality-testing, and ":=" for assignment which feels a little 
closer to mathematical use of "=".


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