Tutorial - section 8.5 -- User Defined Execptions?

Erik Max Francis max at alcyone.com
Thu Apr 17 19:58:44 CEST 2003

Bengt Richter wrote:

> What other use is there (outside of strings and comments)?
> Have we purposely been set up for gaucheries?
> ;-)

In shell-like languages, the backquotes are used to mean "Execute what's
in between the backquotes as a shell command, and then substitute the
(stdout) output of that command and continue, e.g.:

max at oxygen:~% echo The date is: `date` 
The date is: Thu Apr 17 10:54:03 PDT 2003

In modern shells, the form $(...) is preferred to `...`, since the
former can be nested, whereas the latter cannot.

As for Python's use of the backquotes, I presume it's some historical
issue.  I don't know what Guido would say about its use now, but there
seems pretty near total consensus that repr(x) looks a lot better (and
clearer) than `x`.

I do occasionally use `x`, but only when inserting debug statements
since they're set off so obviously.  "Oh, I see backquotes, that
shouldn't stay in there in production code."

 Erik Max Francis / max at alcyone.com / http://www.alcyone.com/max/
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