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Note about fix in list comprehensions.

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Guido van Rossum 2001-10-15 15:53:58 +00:00
parent 1c917072ca
commit a8bcf80e7b
1 changed files with 9 additions and 0 deletions
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@ -22,6 +22,15 @@ Type/class unification and new-style classes
Core
- A very subtle syntactical pitfall in list comprehensions was fixed.
For example: [a+b for a in 'abc', for b in 'def']. The comma in
this example is a mistake. Previously, this would silently let 'a'
iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
Note that [a for a in <singleton>] is a convoluted way to say
[<singleton>] anyway, so it's not like any expressiveness is lost.
- binascii has now two quopri support functions, a2b_qp and b2a_qp.
- readline now supports setting the startup_hook and the pre_event_hook.