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PEP 463: Few more markup fixes 

HGe: Enter commit message.  Lines beginning with 'HG:' are removed.
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Yury Selivanov 2014-02-21 00:08:48 -05:00
parent 0d202d119b
commit 3baaf22f53
1 changed files with 13 additions and 13 deletions
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pep-0463.txt
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@ -752,23 +752,23 @@ LookupError, NameError, ZeroDivisionError). All of these were rejected,
for several reasons.
* First and foremost, consistency with the statement form of try/except
would be broken. Just as a list comprehension or ternary if expression
can be explained by "breaking it out" into its vertical statement form,
an expression-except should be able to be explained by a relatively
mechanical translation into a near-equivalent statement. Any form of
syntax common to both should therefore have the same semantics in each,
and above all should not have the subtle difference of catching more in
one than the other, as it will tend to attract unnoticed bugs.
would be broken. Just as a list comprehension or ternary if expression
can be explained by "breaking it out" into its vertical statement form,
an expression-except should be able to be explained by a relatively
mechanical translation into a near-equivalent statement. Any form of
syntax common to both should therefore have the same semantics in each,
and above all should not have the subtle difference of catching more in
one than the other, as it will tend to attract unnoticed bugs.
* Secondly, the set of appropriate exceptions to catch would itself be
a huge point of contention. It would be impossible to predict exactly
which exceptions would "make sense" to be caught; why bless some of them
with convenient syntax and not others?
a huge point of contention. It would be impossible to predict exactly
which exceptions would "make sense" to be caught; why bless some of them
with convenient syntax and not others?
* And finally (this partly because the recommendation was that a bare
except should be actively encouraged, once it was reduced to a "reasonable"
set of exceptions), any situation where you catch an exception you don't
expect to catch is an unnecessary bug magnet.
except should be actively encouraged, once it was reduced to a "reasonable"
set of exceptions), any situation where you catch an exception you don't
expect to catch is an unnecessary bug magnet.
Consequently, the use of a bare 'except' is down to two possibilities:
either it is syntactically forbidden in the expression form, or it is