[Tutor] Perl Symbology
kent37 at tds.net
Thu Feb 10 19:43:21 CET 2005
Python 2.4 includes a string.Template class which does much the same thing as Itpl.itpl():
>>> from string import Template
>>> s, n, r = '0', 12, 3.4
>>> x = Template("$s $n $r")
'0 12 3.4'
If you want to bundle this up in a pp() function you have to do some magic to get the locals() of
the caller. This seems to work:
>>> import sys
>>> def pp(s):
... loc = sys._getframe(1).f_locals
... print Template(s).substitute(loc)
>>> pp("$s $n $r")
0 12 3.4
Bill Mill wrote:
> I get the impression that many pythonistas don't like string
> interpolation. I've never seen a clear definition of why. Anyway, it's
> easy enough to add with the Itpl  module:
>>>>import Itpl, sys
>>>>sys.stdout = Itpl.filter()
>>>>s, n, r = 0, 0, 0
>>>>print "$s $n $r"
> 0 0 0
>>>>x = Itpl.itpl("$s $n $r")
> '0 0 0'
> And, of course, you can give Itpl.itpl a nicer name; I usually call it
> pp(). If you don't need to change the behavior of the "print"
> statement, then you don't need the Itpl.filter() line.
>  http://lfw.org/python/Itpl.py
> Bill Mill
> bill.mill at gmail.com
> On Thu, 10 Feb 2005 10:22:51 -0500, Smith, Jeff <jsmith at medplus.com> wrote:
>>To all those who talked about hating the symbology in Perl and the
>>suggestion that it should be removed from a later version. I just
>>remembered what you get for that symbology that I really do like about
>>Perl: variable interpolation in strings:
>>sprintf(newstr,"%s %d %f",s,n,r);
>>Becomes a little nicer in Python with:
>>newstr = '%s %d %f' % (s,n,r)
>>Although it's worse with:
>>newstr = s + ' ' + str(n) + ' ' + str(r)
>>But in my mind nothing beats the Perl statement:
>>newstr = "$s $n $r";
>>for clarity, ease of use, and maintainability.
>>Tutor maillist - Tutor at python.org
> Tutor maillist - Tutor at python.org
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