Re: naming convention for scalars, lists, dictionaries ...
[EMAIL PROTECTED] wrote in message news:<[EMAIL PROTECTED]>... > Since Python does not have declarations, I wonder if people think it is > good to name function arguments according to the type of data structure > expected, with names like "xlist" or "xdict". Your suggestion coincides partly with a mechanism I developed recently for my libxml2dom package. The normal libxml2dom package puts a DOM-style wrapper around the existing Python wrapper objects - something that Python's dynamic features accomplish easily - but this incurs a major performance cost. Given that a low-level API (libxml2mod) exists and provides a means to exchange fairly simple and/or opaque objects with the library, I wondered if I couldn't just write a code transformer which takes DOM-like code and emits code to use the low-level API. For example: element.childNodes -> libxml2mod.children(element) The challenge, as you've noted with your mention of declarations, is to find out whether a particular name refers to an object of a suitable type for the kind of transformations I have in mind. (Alternatively, one could just guess that "childNodes" is a DOM-style attribute and do the transformation, possibly leading to mistaken transformations taking place.) Whilst type inference might offer a solution, it is itself a much bigger project than this, so my quick solution was to permit the annotation of names using prefixes to indicate which names refer to DOM-style objects. For example: # Special magic defined earlier says that x2_ is the chosen prefix. x2_element.childNodes -> libxml2mod.children(x2_element) The result of this is libxml2macro [1], an experimental interface to libxml2 which manages to retain much of the space/time performance of that library, albeit without addressing the divisive issues of transparent memory management. It also offers an insight into the "optional static typing" parallel universe for Python... Paul [1] http://www.boddie.org.uk/python/libxml2dom.html -- http://mail.python.org/mailman/listinfo/python-list
Re: naming convention for scalars, lists, dictionaries ...
On Mon, Feb 28, 2005 at 09:41:37PM +0100, Just wrote: > In article <[EMAIL PROTECTED]>, > Jack Diederich <[EMAIL PROTECTED]> wrote: > > > On Mon, Feb 28, 2005 at 04:02:37PM -0500, Benji York wrote: > > > Jack Diederich wrote: > > > >Ditto for me, plural implies list and singular implies instance, > > > >for (contact) in contacts: > > > > # do something with contact > > > > > > May I ask why you place the parenthesis in the for statement? > > > > I like the tuple-ness feel of it and frequently unpack multiple > > values in for loops. I also like the visual feel, it makes it > > easy to see what is being unpacked and what is the source. > > > > "for (one, two, three) in somelist:" > > versus > > "for one, two, three in sometlist:" > > > > Even with a colorizing editor (emacs) I find the first version > > easier to read. YMMV. > > But you're using it for _single_ values. That's like writing > > (val) = someFunction(...) Your Milage May^H^H^HDoes Vary *wink* A quick grep of my source shows zero unparenthesized for loops, 266 with multiple unpacks and 492 iterating over single values. Actually a bit closer to even, 96 are 'for (i) in range(len(l)):' that were written before enumerate() came about. I just always use parenthesis in for loops and when creating/upacking tuples. I find it easier to read, except in the '(var) = func()' case. Other people never use them. *shrug* I find this impossible to get worked up about. What other people do in the privacy of their own codebase doesn't bother me one bit. My $0.01 bits, -Jack -- http://mail.python.org/mailman/listinfo/python-list
Re: naming convention for scalars, lists, dictionaries ...
In article <[EMAIL PROTECTED]>, Jack Diederich <[EMAIL PROTECTED]> wrote: > On Mon, Feb 28, 2005 at 04:02:37PM -0500, Benji York wrote: > > Jack Diederich wrote: > > >Ditto for me, plural implies list and singular implies instance, > > >for (contact) in contacts: > > > # do something with contact > > > > May I ask why you place the parenthesis in the for statement? > > I like the tuple-ness feel of it and frequently unpack multiple > values in for loops. I also like the visual feel, it makes it > easy to see what is being unpacked and what is the source. > > "for (one, two, three) in somelist:" > versus > "for one, two, three in sometlist:" > > Even with a colorizing editor (emacs) I find the first version > easier to read. YMMV. But you're using it for _single_ values. That's like writing (val) = someFunction(...) Just -- http://mail.python.org/mailman/listinfo/python-list
Re: naming convention for scalars, lists, dictionaries ...
On Mon, Feb 28, 2005 at 04:02:37PM -0500, Benji York wrote: > Jack Diederich wrote: > >Ditto for me, plural implies list and singular implies instance, > >for (contact) in contacts: > > # do something with contact > > May I ask why you place the parenthesis in the for statement? I like the tuple-ness feel of it and frequently unpack multiple values in for loops. I also like the visual feel, it makes it easy to see what is being unpacked and what is the source. "for (one, two, three) in somelist:" versus "for one, two, three in sometlist:" Even with a colorizing editor (emacs) I find the first version easier to read. YMMV. -Jack -- http://mail.python.org/mailman/listinfo/python-list
Re: naming convention for scalars, lists, dictionaries ...
Jack Diederich wrote: Ditto for me, plural implies list and singular implies instance, for (contact) in contacts: # do something with contact May I ask why you place the parenthesis in the for statement? -- Benji -- http://mail.python.org/mailman/listinfo/python-list
Re: naming convention for scalars, lists, dictionaries ...
On Mon, Feb 28, 2005 at 11:32:22AM -0700, Steven Bethard wrote: > [EMAIL PROTECTED] wrote: > >Since Python does not have declarations, I wonder if people think it is > >good to name function arguments according to the type of data structure > >expected, with names like "xlist" or "xdict". > > In general, I find that naming collections for their contents is much > more useful than some abbreviated type prefix. However, while I don't > name objects by their type, I do tend to name iterables with plurals > (e.g. "words", "feature_indices", "events", etc.) and I typically suffix > mapping types with "map" (e.g. "word_index_map", "event_relation_map", > "prime_factor_map", etc.) > Ditto for me, plural implies list and singular implies instance, for (contact) in contacts: # do something with contact But I tend to name dictionaries as "key_to_value" as in "email_to_contact" or "ip_to_hostname." for (email) in emails: contact = email_to_contact[email] # do something with contact It may seem verbose but I can type much faster than I can think and it makes reading even forgotten code a breeze. -Jack -- http://mail.python.org/mailman/listinfo/python-list
Re: naming convention for scalars, lists, dictionaries ...
[EMAIL PROTECTED] wrote: Since Python does not have declarations, I wonder if people think it is good to name function arguments according to the type of data structure expected, with names like "xlist" or "xdict". In general, I find that naming collections for their contents is much more useful than some abbreviated type prefix. However, while I don't name objects by their type, I do tend to name iterables with plurals (e.g. "words", "feature_indices", "events", etc.) and I typically suffix mapping types with "map" (e.g. "word_index_map", "event_relation_map", "prime_factor_map", etc.) STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: naming convention for scalars, lists, dictionaries ...
beliavsky> Since Python does not have declarations, I wonder if people beliavsky> think it is good to name function arguments according to the beliavsky> type of data structure expected, with names like "xlist" or beliavsky> "xdict". In general, no. I think variable names should reflect what they are naming, not their types. Skip -- http://mail.python.org/mailman/listinfo/python-list
naming convention for scalars, lists, dictionaries ...
Since Python does not have declarations, I wonder if people think it is good to name function arguments according to the type of data structure expected, with names like "xlist" or "xdict". -- http://mail.python.org/mailman/listinfo/python-list
