Doc fixes. Remove overbroad, redundant warnings. Fixup example code.

This commit is contained in:
Raymond Hettinger 2009-02-04 11:59:49 +00:00
parent e17570d7fd
commit 1e884d9f67
1 changed files with 9 additions and 27 deletions

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@ -298,6 +298,15 @@ Operations which work with sequences include:
This function is removed in Python 3.0. Use :func:`setitem` with a slice
index.
Example use of operator functions::
>>> # Elementwise multiplication
>>> map(mul, [0, 1, 2, 3], [10, 20, 30, 40])
[0, 20, 60, 120]
>>> # Dot product
>>> sum(map(mul, [0, 1, 2, 3], [10, 20, 30, 40]))
200
Many operations have an "in-place" version. The following functions provide a
more primitive access to in-place operators than the usual syntax does; for
@ -455,12 +464,6 @@ abstract base classes instead (see :mod:`collections` and
Returns true if the object *obj* supports the mapping interface. This is true for
dictionaries and all instance objects defining :meth:`__getitem__`.
.. warning::
There is no reliable way to test if an instance supports the complete mapping
protocol since the interface itself is ill-defined. This makes this test less
useful than it otherwise might be.
.. function:: isNumberType(obj)
@ -470,12 +473,6 @@ abstract base classes instead (see :mod:`collections` and
Returns true if the object *obj* represents a number. This is true for all
numeric types implemented in C.
.. warning::
There is no reliable way to test if an instance supports the complete numeric
interface since the interface itself is ill-defined. This makes this test less
useful than it otherwise might be.
.. function:: isSequenceType(obj)
@ -486,21 +483,6 @@ abstract base classes instead (see :mod:`collections` and
for all objects which define sequence methods in C, and for all instance objects
defining :meth:`__getitem__`.
.. warning::
There is no reliable way to test if an instance supports the complete sequence
interface since the interface itself is ill-defined. This makes this test less
useful than it otherwise might be.
Example: Build a dictionary that maps the ordinals from ``0`` to ``255`` to
their character equivalents.
>>> d = {}
>>> keys = range(256)
>>> vals = map(chr, keys)
>>> map(operator.setitem, [d]*len(keys), keys, vals) # doctest: +SKIP
.. XXX: find a better, readable, example
The :mod:`operator` module also defines tools for generalized attribute and item
lookups. These are useful for making fast field extractors as arguments for