Module commitmessage.Itpl
String interpolation for Python (by Ka-Ping Yee, 14 Feb 2000).
(Found Itpl via PEP 215 on 2/10/03 for use in commitmessage...Contacted the
original author and received permission to use Itpl.py for any means.
- Stephen Haberman)
This module lets you quickly and conveniently interpolate values into
strings (in the flavour of Perl or Tcl, but with less extraneous
punctuation). You get a bit more power than in the other languages,
because this module allows subscripting, slicing, function calls,
attribute lookup, or arbitrary expressions. Variables and expressions
are evaluated in the namespace of the caller.
The itpl() function returns the result of interpolating a string, and
printpl() prints out an interpolated string. Here are some examples:
from Itpl import printpl
printpl("Here is a $string.")
printpl("Here is a $module.member.")
printpl("Here is an $object.member.")
printpl("Here is a $functioncall(with, arguments).")
printpl("Here is an ${arbitrary + expression}.")
printpl("Here is an $array[3] member.")
printpl("Here is a $dictionary['member'].")
The filter() function filters a file object so that output through it
is interpolated. This lets you produce the illusion that Python knows
how to do interpolation:
import Itpl
sys.stdout = Itpl.filter()
f = "fancy"
print "Isn't this $f?"
print "Standard output has been replaced with a $sys.stdout object."
sys.stdout = Itpl.unfilter()
print "Okay, back $to $normal."
Under the hood, the Itpl class represents a string that knows how to
interpolate values. An instance of the class parses the string once
upon initialization; the evaluation and substitution can then be done
each time the instance is evaluated with str(instance). For example:
from Itpl import Itpl
s = Itpl("Here is $foo.")
foo = 5
print str(s)
foo = "bar"
print str(s)
| Classes |
Itpl |
Class representing a string with interpolation abilities. |
ItplFile |
A file object that filters each write() through an interpolator. |
| Function Summary |
| |
filter(file)
Return an ItplFile that filters writes to the given file object. |
| |
itpl(text)
|
| |
matchorfail(text,
pos)
|
| |
printpl(text)
|
| |
unfilter(ifile)
Return the original file that corresponds to the given ItplFile. |
filter(file=<epydoc.imports._DevNull instance at 0x00B9F5D0>)
Return an ItplFile that filters writes to the given file object.
'file = filter(file)' replaces 'file' with a filtered object that
has a write() method. When called with no argument, this creates a
filter to sys.stdout.
-
|
unfilter(ifile=None)
Return the original file that corresponds to the given ItplFile.
'file = unfilter(file)' undoes the effect of 'file = filter(file)'.
'sys.stdout = unfilter()' undoes the effect of 'sys.stdout =
filter()'.
-
|
