Re: [Python-ideas] parameter omit
Adding python-ideas in as a CC, because I'm a jerk. "Aaron Brady" <castironpi@comcast.net> wrote:
Post what you want. If people aren't offering +1 or -1, it could be for any number of reasons; from being busy (it is in the middle of the week), to just not caring enough either way, believing that their opinions and interests are already being expressed, etc. But when you post something, then 24 hours and 40 minutes later you ask, "Also, any follow-up on this? (I posted at top.)" at the bottom of a 95 line quote of your own last post without cutting out the unimportant parts, it is pestering, and a very low signal to noise ratio 1:95. Never mind that you only recently seemed to learn that we don't top post in Python mailing lists, but you still haven't realized that we trim unimportant parts of quoted posts. Had you top posted or failed to trim either in python-list (or the equivalent comp.lang.python), any number of people would have told you as much. But hey, you are being such the good usenet poster, you couldn't have made a mistake, of course not. Get over yourself. With that said, I don't particularly like the addition of syntax for something that can already be done other ways (TOOWTDI), or the addition of a new builtin to signal something that I've never heard *anyone* ask about before. Really, the only *reasonable* name is 'default', which is used at least 146 times in the Python standard library (according to my regular expression of default\s*=), and I'm sure thousands of times in 3rd party code. It would necessitate a huge change for a feature that no one (but you) as asked for so that you can use... foo(a, b=default, c=1234) foo(a, b=253463, c=default) rather than... foo(a, c=1234) foo(a, b=253463) Personally, I find the latter more consistant (only pass arguments that you care to change). If you don't, that's fine. The burdon of proof isn't on me, or anyone else in python-ideas to prove to you that your idea sucks; it's on you to prove to everyone else that your idea *doesn't* suck. Good luck on that. Local jerk, - Josiah
Correct, signal to noise, content to form. My idea came in a slightly unconventional format. Not posting in Hebrew or something. Besides, that problem cleared itself up on its own. I noticed I wasn't blending in. Within a full 24 hours, I expect an, "I like this, may be good. Here's my personal e-mail address, get back to me in a week if you haven't heard anything." No elaboration is necessary at this point. It only takes one day to write this. But that's just where I come from. So instead, I pursue and follow-up on my own initiative. Does need a reply of some sort or another. Lastly, most importantly, you misunderstand the issue. The example says it all, but I'm willing to explain, just for the asking. Don't misquote me, but the trade-off follows. Three-line function definition [Carlson 19:59 American Central Time] versus one. More than three lines if you have more than three parameters: one line per parameter. Cobol is another way to do it, so be careful with acronyms. No new syntax in this one. The old ways: [code to assign my_b and my_c] if use_default_b and use_defualt_c: foo(a) elif use_default_b: foo(a, c=my_c) elif use_default_c: foo(a, my_b) -or- def foo(arg1, **kwargs): arg2 = kwargs.get('arg2', 1.2325) arg3 = kwargs.get('arg3', 'hello') The new way: my_b, my_c= paramdefault, paramdefault [code to assign my_b and my_c] foo(a, my_b, my_c) And don't get me started on `d'. ParamDefault is like True, False, and None. Not traditional, in truth, Pythonic. Looking far into the future, however, I suppose it could start to get abused, like putting None in dictionaries, for example. Perhaps it was None's original intent. Fellow jerk, - Aaron [p.s. { 'akey': ParamDefault }, ha]
On 5/10/07, Aaron Brady <castironpi@comcast.net> wrote:
As another poster mentioned, the normal way to write this is:: kwargs = {} if use_default_b: kwargs['b'] = my_b if use_default_c: kwargs['c'] = my_c foo(a, **kwargs) It is so extremely uncommon to need to do such a thing that I'm firmly against adding any additional syntax. Syntax should only be introduced for common things that many people need. STeVe -- I'm not *in*-sane. Indeed, I am so far *out* of sane that you appear a tiny blip on the distant coast of sanity. --- Bucky Katt, Get Fuzzy
Mr. Bethard, I am not adding syntax. Don't put words in my mouth. This is another one- observe the subject line. Tell me you always make a call with the same parameters, every time you make the call. My thinking can't be that backwards. A use case could take some time, but sure.
Steve, Take a shot at this one. class WebRetrieveElement: def netretrieveOld( self ): if hasattr( self,'hook' ) and self.filename: urlretrieve( self.url, self.filename, self.hook ) elif hashook: urlretrieve( self.url, reporthook= self.hook ) else: urlretrieve( self.url, self.filename ) def netretrieveNew( self ): filename= self.filename or ParamDefault hook= hasattr( self,'hook' ) and self.hook or ParamDefault urlretrieve( self.url, filename, hook ) What is the default parameter for the function? Problem is, the docs don't say what it is. Does it pick its own filename to use for empty inputs?
"Aaron Brady" <castironpi@comcast.net> wrote:
What is the default parameter for the function? Problem is, the docs don't say what it is. Does it pick its own filename to use for empty inputs?
>>> import urllib >>> help(urllib.urlretrieve) Help on function urlretrieve in module urllib: urlretrieve(url, filename=None, reporthook=None, data=None) >>> - Josiah
Correct, signal to noise, content to form. My idea came in a slightly unconventional format. Not posting in Hebrew or something. Besides, that problem cleared itself up on its own. I noticed I wasn't blending in. Within a full 24 hours, I expect an, "I like this, may be good. Here's my personal e-mail address, get back to me in a week if you haven't heard anything." No elaboration is necessary at this point. It only takes one day to write this. But that's just where I come from. So instead, I pursue and follow-up on my own initiative. Does need a reply of some sort or another. Lastly, most importantly, you misunderstand the issue. The example says it all, but I'm willing to explain, just for the asking. Don't misquote me, but the trade-off follows. Three-line function definition [Carlson 19:59 American Central Time] versus one. More than three lines if you have more than three parameters: one line per parameter. Cobol is another way to do it, so be careful with acronyms. No new syntax in this one. The old ways: [code to assign my_b and my_c] if use_default_b and use_defualt_c: foo(a) elif use_default_b: foo(a, c=my_c) elif use_default_c: foo(a, my_b) -or- def foo(arg1, **kwargs): arg2 = kwargs.get('arg2', 1.2325) arg3 = kwargs.get('arg3', 'hello') The new way: my_b, my_c= paramdefault, paramdefault [code to assign my_b and my_c] foo(a, my_b, my_c) And don't get me started on `d'. ParamDefault is like True, False, and None. Not traditional, in truth, Pythonic. Looking far into the future, however, I suppose it could start to get abused, like putting None in dictionaries, for example. Perhaps it was None's original intent. Fellow jerk, - Aaron [p.s. { 'akey': ParamDefault }, ha]
On 5/10/07, Aaron Brady <castironpi@comcast.net> wrote:
As another poster mentioned, the normal way to write this is:: kwargs = {} if use_default_b: kwargs['b'] = my_b if use_default_c: kwargs['c'] = my_c foo(a, **kwargs) It is so extremely uncommon to need to do such a thing that I'm firmly against adding any additional syntax. Syntax should only be introduced for common things that many people need. STeVe -- I'm not *in*-sane. Indeed, I am so far *out* of sane that you appear a tiny blip on the distant coast of sanity. --- Bucky Katt, Get Fuzzy
Mr. Bethard, I am not adding syntax. Don't put words in my mouth. This is another one- observe the subject line. Tell me you always make a call with the same parameters, every time you make the call. My thinking can't be that backwards. A use case could take some time, but sure.
Steve, Take a shot at this one. class WebRetrieveElement: def netretrieveOld( self ): if hasattr( self,'hook' ) and self.filename: urlretrieve( self.url, self.filename, self.hook ) elif hashook: urlretrieve( self.url, reporthook= self.hook ) else: urlretrieve( self.url, self.filename ) def netretrieveNew( self ): filename= self.filename or ParamDefault hook= hasattr( self,'hook' ) and self.hook or ParamDefault urlretrieve( self.url, filename, hook ) What is the default parameter for the function? Problem is, the docs don't say what it is. Does it pick its own filename to use for empty inputs?
"Aaron Brady" <castironpi@comcast.net> wrote:
What is the default parameter for the function? Problem is, the docs don't say what it is. Does it pick its own filename to use for empty inputs?
>>> import urllib >>> help(urllib.urlretrieve) Help on function urlretrieve in module urllib: urlretrieve(url, filename=None, reporthook=None, data=None) >>> - Josiah
participants (3)
-
Aaron Brady -
Josiah Carlson -
Steven Bethard