terminology in the alpha 1 documentation.
- "context manager" reverts to its alpha 1 definition
- the term "context specifier" goes away entirely
- contextlib.GeneratorContextManager is renamed GeneratorContext
There are still a number of changes relative to alpha 1:
- the expression in the with statement is explicitly called the
"context expression" in the language reference
- the terms 'with statement context', 'context object' or 'with
statement context' are used in several places instead of a bare
'context'. The aim of this is to avoid ambiguity in relation to the
runtime context set up when the block is executed, and the context
objects that already exist in various application domains (such as
decimal.Context)
- contextlib.contextmanager is renamed to contextfactory
This best reflects the nature of the function resulting from the
use of that decorator
- decimal.ContextManager is renamed to WithStatementContext
Simple dropping the 'Manager' part wasn't possible due to the
fact that decimal.Context already exists and means something
different. WithStatementContext is ugly but workable.
A technically unrelated change snuck into this commit:
contextlib.closing now avoids the overhead of creating a
generator, since it's trivial to implement that particular
context manager directly.
- The copy module now "copies" function objects (as atomic objects).
- dict.__getitem__ now looks for a __missing__ hook before raising
KeyError.
- Added a new type, defaultdict, to the collections module.
This uses the new __missing__ hook behavior added to dict (see above).
* explanation for example with lists of lists made confusing use of
the word "contains" to mean "is built out of".
* wrong formula for slices with step. Is it ok to use LaTeX formulas
(which become images in the html document)? This version needs one
because it's based on a fraction. Just writing "\code{(j-i)/k}" here would
be ambiguous because it looks like a rounding-down-to-the-previous-integer
division, which is not what we need here. Of course we could write
"\code{float(j-i)/k}" but it just looks confusing.
* Discuss the algorithmic distinctions between s.split() and s.split(sep).
* Document the split behavior for empty strings.
* Note the behavior when maxsplit is zero.
* Include short examples.
unicodedata.east_asian_width(). You can still implement your own
simple width() function using it like this:
def width(u):
w = 0
for c in unicodedata.normalize('NFC', u):
cwidth = unicodedata.east_asian_width(c)
if cwidth in ('W', 'F'): w += 2
else: w += 1
return w
Georg Brandl
Nick Coghlan
Fred Drake
Phillip J. Eby
Neal Norwitz
Guido van Rossum
Walter Dörwald
Raymond Hettinger
Armin Rigo
Andrew M. Kuchling
Michael W. Hudson
Hye-Shik Chang
Skip Montanaro