On 08/18/10 04:50, Cameron Simpson wrote:
("nikos",) is a single element tuple.
["nikos"] is a single element list.
["nikos",] is also a single element list, just written like the tuple.
You don't see the ["nikos",] form very often because ["nikos"] is not
ambiguous.
I most frequently see/use the trailing comma in a one-item list
when I expect additional items will be accrued later, so it makes
my version-control diffs tidier:
items = [
"nikos",
]
Then a month later, I add
items = [
"nikos",
"cameron",
]
My diff is just
items = [
"nikos",
+ "cameron",
]
which is quite easy to understand. However if my original was
items = [
"nikos"
]
and I later want to make it
items = [
"nikos",
"cameron"
]
the diff then becomes
items = [
- "nikos"
+ "nikos",
+ "cameron"
]
which isn't nearly as easy to read & understand because I now
have to notice the inter-linear differences ("did something more
than the new-comma happen?").
-tkc
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