On Mon, Apr 24, 2006, Phillip J. Eby wrote: > At 12:49 PM 4/24/2006 -0700, Aahz wrote: >>On Mon, Apr 24, 2006, Phillip J. Eby wrote: >>> At 12:24 PM 4/24/2006 -0700, Aahz wrote: >>>>On Mon, Apr 24, 2006, Phillip J. Eby wrote: >>>>> At 04:48 AM 4/25/2006 +1000, Nick Coghlan wrote: >>>>>> >>>>>>Using two names to describe three different things isn't intuitive for >>>>>>anybody. >>>>> >>>>> Um, what three things? I only count two: >>>>> >>>>> 1. Objects with __context__ >>>>> 2. Objects with __enter__ and __exit__ >>>>> >>>>> What's the third thing? >>>> >>>>The actual context that's used during the execution of BLOCK. It does >>>>not exist as a concrete object, >>> >>> Um, huh? It's a thing but it's not an object? I'm lost now. I don't see >>> why we should introduce a concept that has no concrete existence into >>> something that's hard enough to explain when you stick to the objects that >>> actually exist. :) >> >>Let's go back to a pseudo-coded with statement: >> >> with EXPRESSION [as NAME]: >> BLOCK >> >>What happens while BLOCK is being executed? Again, here's what I said >>originally: >> >> EXPRESSION returns a value that the with statement uses to create a >> context (a special kind of namespace). The context is used to >> execute the BLOCK. The block might end normally, get terminated by >> a break or return, or raise an exception. No matter which of those >> things happens, the context contains code to clean up after the >> block. >> >>Do you have an alternate proposal for describing this that works well for >>newbies? > > No, I like your phrasing -- but it's quite concrete. EXPRESSION returns a > value (object w/__context__) used to create a context (object w/__enter__ > and __exit__). > > That's only two things. There is no *third* thing here.
What is EXPRESSION, then? Not the value it returns, but EXPRESSION itself -- does it have a name? What about the kinds of things we use for EXPRESSION? -- Aahz ([EMAIL PROTECTED]) <*> http://www.pythoncraft.com/ "Argue for your limitations, and sure enough they're yours." --Richard Bach _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
