On Fri, 07 Mar 2008 12:38:11 -0800, waltbrad wrote: > The script comes from Mark Lutz's Programming Python. It is the second > line of a script that will launch a python program on any platform. > > import os, sys > pyfile = (sys.platform[:3] == 'win' and 'python.exe') or 'python' > > Okay, run on a win32 machine, pyfile evaluates to python.exe > > That makes sense. Because the first condition is true and 'python.exe' > is true. So the next comparison is 'python.exe' or 'python' Well, > python.exe is true. So that value is returned to pyfile. > > Now. Run this on linux. The first condition evaluates sys.platform[:3] > == 'win' as false. So, the next comparison should be 'False' or > 'python' -- This is because 'and' returns the first false value. But, > again, on linux pyfile evaluates to python.exe
Not on my Linux box. >>> import os, sys >>> sys.platform 'linux2' >>> (sys.platform[:3] == 'win' and 'python.exe') or 'python' 'python' > Where am I going wrong. And when will this statment make pyfile > evaluate to 'python' ? When the first three letters of sys.platform aren't 'win'. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
