converting a sed / grep / awk / . . . bash pipe line into python

[Roy Smith]

In article <g9m6at$a71$01$1 at news.t-online.com>,
 Peter Otten <__peter__ at web.de> wrote:

> Roy Smith wrote:
> 
> > In article <g9lvc5$8qq$03$1 at news.t-online.com>,
> >  Peter Otten <__peter__ at web.de> wrote:
> > 
> >> > I might take it one step further, however, and do:
> >> > 
> >> >>         fields = line.split()[:2]
> >> >>         a, b = map(int, fields)
> >> > 
> >> > in fact, I might even get rid of the very generic, but conceptually
> >> > overkill, use of map() and just write:
> >> > 
> >> >>         a, b = line.split()[:2]
> >> >>         a = int(a)
> >> >>         b = int(b)
> >> 
> >> If you go that route your next step is to introduce another try...except,
> >> one for the unpacking and another for the integer conversion...
> > 
> > Why another try/except?  The potential unpack and conversion errors exist
> > in both versions, and the existing try block catches them all.  Splitting
> > the one line up into three with some intermediate variables doesn't change
> > that.
> 
> As I understood it you didn't just split a line of code into three, but
> wanted two processing steps. These logical steps are then somewhat remixed
> by the shared error handling. You lose the information which step failed.
> In the general case you may even mask a bug.
> 
> Peter

Well, what I really wanted was two conceptual steps, to make it easier for 
a reader of the code to follow what it's doing.  My standard for code being 
adequately comprehensible is not that the reader *can* figure it out, but 
that the reader doesn't have to exert any effort to figure it out.  Or even 
be aware that there's any figuring-out going on.  He or she just reads it.