@@ -972,12 +972,13 @@ Use of alternative formatting styles
972972When logging was added to the Python standard library, the only way of
973973formatting messages with variable content was to use the %-formatting
974974method. Since then, Python has gained two new formatting approaches:
975- string.Template (added in Python 2.4) and str.format (added in Python 2.6).
975+ :class: `string.Template ` (added in Python 2.4) and :meth: `str.format `
976+ (added in Python 2.6).
976977
977- Logging now (as of 3.2) provides improved support for these two additional
978- formatting styles. The :class: `Formatter ` class been enhanced for Python 3.2 to
979- take an additional, optional keyword parameter named ``style ``. This defaults
980- to ``'%' ``, but other possible values are ``'{' `` and ``'$' ``, which correspond
978+ Logging (as of 3.2) provides improved support for these two additional
979+ formatting styles. The :class: `Formatter ` class been enhanced to take an
980+ additional, optional keyword parameter named ``style ``. This defaults to
981+ ``'%' ``, but other possible values are ``'{' `` and ``'$' ``, which correspond
981982to the other two formatting styles. Backwards compatibility is maintained by
982983default (as you would expect), but by explicitly specifying a style parameter,
983984you get the ability to specify format strings which work with
@@ -1068,7 +1069,7 @@ they're declared in a module called ``wherever``):
10681069.. code-block :: pycon
10691070
10701071 >>> from wherever import BraceMessage as __
1071- >>> print(__('Message with {0} {1 }', 2, 'placeholders'))
1072+ >>> print(__('Message with {0} {name }', 2, name= 'placeholders'))
10721073 Message with 2 placeholders
10731074 >>> class Point: pass
10741075 ...
@@ -1083,6 +1084,10 @@ they're declared in a module called ``wherever``):
10831084 Message with 2 placeholders
10841085 >>>
10851086
1087+ While the above examples use ``print() `` to show how the formatting works, you
1088+ would of course use ``logger.debug() `` or similar to actually log using this
1089+ approach.
1090+
10861091One thing to note is that you pay no significant performance penalty with this
10871092approach: the actual formatting happens not when you make the logging call, but
10881093when (and if) the logged message is actually about to be output to a log by a
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