(test) ? a:b

Ben Finney ben+python at benfinney.id.au
Mon Oct 27 01:38:13 CET 2014


Steven D'Aprano <steve+comp.lang.python at pearwood.info> writes:

> Do you really not see the connection between counting and summing?

Connection? Of course. But I also see a huge distinction. I'm surprised
you could misunderstand my position to the extent you think such a
question needs to be asked.

The difference between “sum these values” versus “count these values” is
important. That's at the root of why I find it confusingly wrong to sum
True or False values.

Do you really not see the distinction between counting and summing?

The question is just as silly that way.

> If you have three apples, and I have two apples, then in total we have
> (count the apples: one two three, four five) five apples.

If you have three apples in one basket, and I have two apples in one
basket, “sum the baskets” is quite a different operation from “count the
baskets”.

    [3, 2]

What is the sum of those values?

How many values are there?

The distinction between those is why I find it unhelpful to express “how
many values?” with “sum them”.

> Alas, you missed the bigger bug: I'm counting *blank lines*, not
> non-blank lines. You need a `not` in there.

Which is, shall we say, not incompatible with the position that the
“count the matches by summing bools” method is an unclear expression of
intent :-)

-- 
 \     “Sittin' on the fence, that's a dangerous course / You can even |
  `\       catch a bullet from the peace-keeping force” —Dire Straits, |
_o__)                                   _Once Upon A Time In The West_ |
Ben Finney




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