aklei...@sonic.net wrote:
> Part of a previous post:
> """
> Here's the style I'd use:
>
> combos = {
> 0: 'id',
> 2: 'country',
> 3: 'type',
> 5: 'lat',
> 6: 'lon',
> 12: 'name',
> }
>
> Put each entry on its own line, indented by two spaces, and leave a
> trailing comma on the last entry. The latter is especially important
> in sequences of strings to prevent them from being
> "silently"<=>"concatenated" if you were to add an entry and forget the
> comma.
> """
>
> When I first saw this I thought it would lead to a syntax error so tried
> it out..
> Then played with it to try to recreate the '"silently"<=>"concatenated"'
> problem but couldn't. I like this syntax because it avoids the syntax
> error if the comma is omitted when adding an entry but I don't understand
> the (potential) concatenation problem.
>
> Could you explain please?
Consider the following list:
>>> ["the"
... "quick",
... "brown"
... "fox"]
['thequick', 'brownfox']
"the" and "quick" look like two entries in the list, but as the comma is
missing they are merged together. Same for "brown" and "fox".
I think you cannot run into this problem with dictionaries as accidentally
merging a value and a key would result in a syntax error at the second
colon:
>>> {"the": "quick"
... "brown": "fox"}
File "<stdin>", line 2
"brown": "fox"}
^
SyntaxError: invalid syntax
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