Extending Python Syntax with @

[David MacQuigg]

Hey guys, let's not go in four different directions and waste all this
bandwidth on debating the four examples I gave.  Everyone has
different ideas on enhancing the language.  If you believe this is a
bad idea, regardless of the particular examples, let's talk.

If you believe as I do that Python is not yet the ultimate language,
and some syntactical changes are still to come, then it seems like
using a very distinct symbol like @ may have some merits.  This is not
a suggestion to make the language "perlesque".  The difference is that
@ not a menagerie of symbols with various tricky meanings, but one
very noticable and unique symbol that says "Pay attention, I am
different."  It has no other meaning.

Wouldn't it be nice, for example, if instead of special keywords like
'lambda' and 'yield', we had used '@(args)' and '@return'.  ( No, I'm
not advocating we go back and change what has been done.)  In both
these cases, we had a well-established syntax that needed a slight
variation.  

The 'lambda function' for example, was needed to cram a small block of
code into a tight space.  By saying '@x,y:' instead of 'lambda x,y:',
we not only avoid the need for a new keyword, but we better serve the
purpose of tightly packing some code.  We would also avoid mystifying
beginners.  "It has no magic meaning.  It's just a way to write a
function without a name."

Sorry if my intentions weren't clear in my original post.

-- Dave

On Wed, 10 Mar 2004 14:01:00 -0700, David MacQuigg <dmq at gain.com>
wrote:

>Seems like we need a simple way to extend Python syntax that doesn't
>break existing syntax or clash with any other syntax in Python, is
>easy to type, easy to read, and is clearly distinct from the "base"
>syntax.  Seems like we could put the @ symbol to good use in these
>situations.  Examples:

[ add your own examples here ]

>Each of these examples is debatable, but my point is that there are
>many enhancement requests like this, and some may be worthy of
>inclusion in the core language.  It would be nice if there was a
>consistent way to add stuff like this.  It certainly beats adding ugly
>statements like 'lambda'.
>
>It might even be possible to allow limited extension of the language
>by users, provided the extensions are introduced by the special
>symbol.  This would allow the flexibility of Ruby or Lisp without the
>cost of forking the language into many dialects.
>
>Maybe we should collect a bunch of little enhancements like the above,
>and put them all into one PEP.  Any suggestions?  Pet peeves?  Stuff
>you would like to see, but not worthy of a PEP by itself?