[Tutor] automatically extending PYTHONPATH?
I am using Python 2.4/IDLE on WinXP. I organize my sourcefiles in a directory tree, similar to the convention used in Java. When I create a new subdirectory, though, I have to either (i) manually edit my PYTHONPATH environment variable, or (ii) do a sys.append() in IDLE for the new scripts to be visible. Is there a workaround for this? For example, is there a setting in IDLE of Python to specify a root source directory and have all subdirectories added automatically? Hope this makes sense, and that a brilliant mind has a quick solution! Thanks, Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] import statements in functions?
Is there a convention to be considered for deciding if import statements should be included in a function body? For example, which of these two module layouts would be preferable: # --- MyModule1.py - import foo1, foo2, foo3 import foo_special # several coherent functions here def specialFunction(): doSomethingSpecial() or the "embedded import" version: # --- MyModule2.py - import foo1, foo2, foo3 import foo_rare # several coherent functions here def specialFunction(): import foo_special doSomethingSpecial() Also, does the choice have any impact on performance/space/etc.? And will the import function get called each time (and possibly ignored) in the second version? The reason I consider the second form is that the module foo_special is only used by the code in specialFunction(), and detracts (IMHO) from understanding the rest of the code in the module. Thanks, Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] python console, IDLE startup scripts
Is there a special startup script the command-line python IDE and/or IDLE use? As per Liam's response to my previous post, I would like to use os.walk() to automatically set my sys.path() variable... Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] a FIFO with fixed capacity?
I need to implement a FIFO with a fixed maximum capacity. Is there a name for such a beast? Also, I read two excellent cookbook recipes on FIFOs: http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/68436 http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/210459 Would limiting the max capacity of the FIFO improve performance by allowing one to preallocate the FIFO buffer? All comments appreciated! Thanks, Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] a FIFO with fixed capacity?
Danny,
Thanks for the informative response. After I sent the email I
realized that a circular buffer is a FIFO with fixed capacity, and
that is what I want to implement. I think I recall seeing a recipe in
the Python Cookbook (1st).
If you or anyone else know of other recipes/implementations please let
me know so I can save on the cut-and-paste. :)
Marcus
ps -- as for the need for a circular buffer vs. FIFO: I think my dsp
background pushed me toward the CB. My app involves data acquisition
for extended periods of time. I can't grow the FIFO infinitely, but
it is no big deal if a few samples get overwritten. Does this make
sense?
On Thu, 31 Mar 2005 01:19:24 -0800 (PST), Danny Yoo
<[EMAIL PROTECTED]> wrote:
>
>
> On Wed, 30 Mar 2005, Marcus Goldfish wrote:
>
> > I need to implement a FIFO with a fixed maximum capacity.
>
> Hi Marcus,
>
> Out of curiosity, why do you require a first-in-first-out queue with a
> maximum capacity?
>
>
> > Would limiting the max capacity of the FIFO improve performance by
> > allowing one to preallocate the FIFO buffer?
>
> Possibly, but at the cost of having a FIFO that can get full. Depending
> on the domain, this might be ok for you. But most programs suffer from
> hardcoded limits that really shouldn't have been hardcoded in the first
> place. You may want to see if having a queue with unlimited size is
> really a performance drag on your system: have you done any profiling yet?
>
> The second implementation that you quoted earlier:
>
> > http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/210459
>
> is similar to a nicer one by Jeremy Fincher:
>
> ##
> class ListSubclassFifo(list):
>__slots__ = ('back',)
>def __init__(self):
>self.back = []
>def enqueue(self, elt):
>self.back.append(elt)
>def dequeue(self):
>if self:
>return self.pop()
>else:
>self.back.reverse()
>self[:] = self.back
>self.back = []
>return self.pop()
> ##
>
> (See: http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/68436)
>
> Since these implementations guarantee O(1) "constant" time access for a
> queue, even without a hardcoded bound limit, you aren't losing much. Can
> you use this implementation?
>
> Finally, there's a 'deque' in the 'collections' Standard Library module
> that you might be able to use:
>
>http://www.python.org/doc/lib/module-collections.html
>
> which also should define constant-time guarantees for insertion and
> removal. So you might just be able to use that, and not have to
> copy-and-paste any code at all. *grin*
>
> Best of wishes to you!
>
>
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Re: [Tutor] a FIFO with fixed capacity?
> Let me make sure I understand. Let's imagine that we have such a > CircularQueue, with methods: > >push(element) >pop() >isEmpty() > > [example unittest code] Danny, Yes, it looks like that is a valid unittest for a circular buffer. An enhancement is to modify the accessors: push(element) --> push(sequence) pop() --> pop(N) If pushing caused an overwrite, the consumer could be notified, perhaps by an overwrite exception. Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] when to use properties?
Are there guidelines for when properties should be used vs. instance variables? For example, it often seems more convenient to directly use instance variables instead of properties, like MyClass2 listed below. Is one class more pythonic than the other? # Example 1: class w/props vs. no-propt class MyClass1(object): def __init__(self, value=0): self._value = value def getValue(self): return self._value def setValue(self, value): self._value = value value = property(getValue, setValue) class MyClass2(object): def __init__(self, value=0): self.value = value x1 = MyClass1(3) x1.value = 3 # same as this? x2 = MyClass2(3) x2.value = 3 On the other hand, I can see how classes that dynamically generate "properties" might find the construct convenient: # Example 2: properties "on-the-fly" import math class RightTriangle(object): def __init__ (self, a=3, b=4): self.a = a self.b = b def getHypotenuse(self): return sqrt(a**2 + b**2) hypotenuse = property(getHypotenuse) t = RightTriangle() t.hypotenuse # returns 5.0 But in Example2 it's still not clear to me whether properties buy anything-- why not just use the getter function? Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Re: when to use properties?
Thanks for all of the comments! The general theme of "don't use a
property unless you need to" is intuitive, and is what I was hoping
the consensus would be.
This raised another design issue for me, tho', regarding property
validation. In C#/Java, I would typically do validation in all of my
setter methods, but is this really pythonic? It seems OO--
encapsulation-- but also seems to be one of the biggest wastes of
coding time & typing in those languages.
As a simple example, consider the following class:
# Example: mixing instance attributes with properties. Is it pythonic to
# validate property data in setters? Note that tens and ones are never
# validated, so the class can break by setting these directly...
class SillyDecimal(object):
def __init__(self, arg=17):
if isinstance(arg, tuple):
self.tens = arg[0]
self.ones = arg[1]
else:
self.number = arg
def getNumber(self):
return self.tens*10 + self.ones
def setNumber(self, value):
if value < 0 or value > 99:
raise ArgumentException("Must in [0, 99]")
self.tens = value // 10
self.ones = value % 10
number = property(getNumber, setNumber, None, "Complete number, [0-99]")
x = SillyDecimal()
x.number, x.tens, x.ones# returns (17, 7, 1)
Notice that while "tens", "ones" and "number" all appear as
attributes, only "number" has its input validated. Since the class is
designed to only hold numbers 0 - 99, one can 'break' it by setting
self.tens=11, for example. Of course this is just a toy example, but
the point should be clear: when is it pythonic to do
attribute/property validation?
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[Tutor] iterator question for a toy class
I'm trying to understand custom iterators in Python, and created the following toy class for sequence comparison, which seems to work: class Foo(object): """A toy class to experiment with __eq__ and __iter__""" def __init__(self, listA, listB): self.head, self.tail = listA, listB def __iter__(self): return iter(self.head[:]+self.tail[:]) def __eq__(self, other): """Foo instances are equal if their respective subsequences, head, tail, are in the same order""" diff = [i for i, j in zip(self, other) if i != j] return len(diff) == 0 >>> f1 = Foo( [1,2], ['a','b','c'] ) >>> f2 = Foo( [1,2], ['a','b','c'] ) >>> f3 = Foo( [1,2], ['a','b','d'] ) >>> f1 == f2, f1 == f3 (True, False) I'm not really sure if I'm implementing iter() correctly, for instance: should I make copies of the sublists? Should I try to implement my own next() method? Advice, comments, and links to good tutorial web pages on iterators are appreciated! Thanks, Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Tracking URL in browser location bar
> > A newbie here..I was wondering if python can help me to track the URL in > > browser (IE6+, FF, Mozilla) location bar. I think browser helper objects may also be useful. ASPN has a thread at: http://aspn.activestate.com/ASPN/Mail/Message/ctypes-users/2263094 Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] iterator question for a toy class
> - As Rich pointed out, making Foo into it's own iterator by adding a next() > method is not a good idea. A simple way to define your own iterator is to I see that an iterator is conceptually distinct from the container object it iterates over, but I am confused that both the iterator and container implement __iter__() to support the iterator protocol. In my original Foo implementation, __iter__() returned a list, which supports the iterator protocol, so it "just worked" (albeit not for all cases, and not efficiently). In general, though, how would I implement my own iterator (not using generator functions)? Would I have to have a FooIterator class? What would FooIterator.__iter__() return? > make __iter__() into a generator function like ... so gfs look much easier! This is the first concrete use for gf's I've found in my code so far, and it rocks-- is it always possible to implement an iterator using gfs? Is there a performance issue to be aware of when using gfs? > you want. A simple definition for __eq__() that finds these unequal would be > def __eq__(self, other): > return self.head == other.head and self.tail == other.tail Ok, I like the modified __eq__(), but now I want my Foo class to store the head and tail lists as private attributes (self.__head, self.__tail). Is it pythonic to modify the __eq__() method to: def __eq__(self, other): return self.__head == other._Foo__head and self.__tail == other._Foo__tail or is this too restrictive (e.g., perhaps I wish to compare a Foo and Bar class as correlated list sequences. It is likely that other._Foo__head will fail for a Bar). > - If you define __eq__() you should also define __ne__(). Alteratively you can ... because it seems that Foo1 != Foo2 will fail otherwise. Why is that? Thanks (you too, Rich) for the very helpful comments! Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] a generic table data structure for table / 2d array / lookup table?
Before I try to reinvent the wheel, can anyone point me to a data
structure suitable for storing non-numeric, 2-d arrays. For instance,
something that can store the following:
A B C D
1 'cat' 3object 9
J4 [1] 56
where the column and row labels in this example are ['A','B','C','D']
and [1,'J'], respectively. I need to access (set and get values) by
cell, row, and column.
I have a solution using 2-tuple keys and a dict, e.g., d[('A',1)], but
it seems kludgy and doesn't handle the row/column access.
Any pointers or code snippets would be appreciated!
Marcus
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[Tutor] super() and inherited attributes?
Hi,
The following example doesn't work as I would like-- the child
instance doesn't expose the attribute set in the parent. Can someone
point out what I am missing?
Thanks,
Marcus
class Parent(object):
def __init__(self, name="I am a parent"):
self.name = name
class Child(Parent):
def __init__(self, number):
super(Parent, self).__init__("I am a child")
self.number = number
# I would like it to produce the following:
>> c = Child(23)
>> c.number
23
>> c.name
"I am a child"
# but I 'AttributeError: 'Child' object has no attribute 'name''
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[Tutor] file io: reading an int32 at the end of a file?
Hi, I have a file format that ends in a 4-byte (int32) number. I would like to read this value in python on a WinXP machine with something like: fname = 'somefile' f = open(fname, 'rb') f.seek(-4,2) offset = f.read() ... but this doesn't seem to work. The value that Python returns is: '@\x19\x01\x00' but I know from similar code in Matlab that the correct sequence is: 64 25 1 0 Can someone point out my error? Thanks! Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] tricky eval() problem
Here's a noodler I could use some help on: I need a class that can
call a user-specified function with arbitrary (unknown) parameter
lists. The trick, here, is that the user will dynamically specify the
funciton to invoke, and each function may differ in the number of
parameters passed during the call. For instance, suppose I define two
dummy functions with different calling signatures:
def foo1(a1, a2, a3):
...
def foo2(a1):
...
Then I seek a class, Caller
class Caller(object):
def execute(self, method, *parms):
# some way to execute method
That can be used in the following manner:
>> c = Caller();
>> c.execute("foo1", 8, 9, 10)
>> c.execute("foo2", "me")
Any tips on tackling this?
Thanks!
Marcus
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[Tutor] stopping threads?
I'm a little confused about threading in Python. Here is a sample class I've written for monitoring for events. Included in the comments are a couple of questions, specifically: (1) can I use super() in the constructor, or is direct call to base class preferred? (2) do I need to sleep in the run() method? If so, why? It seems to improve my programs responsiveness (3) what happens after run() finishes-- does the thread die, get suspended, go away? Should I try to force the thread into one of these states, and if so how? Any help is appreciated! Thanks, Marcus class Monitor(threading.Thread): def __init__(self): threading.Thread.__init__(self) # would super() also work here? which is preferred self.undetected = True # presumably, when the event occurs it sets this attribute to False def run(self): print "looking for event" while self.undetected is True: time.sleep(0.1) # another minor point: why do I need to sleep here? self.processEvent() # what happens here-- does the thread die? def processEvent(self): print "yeah-- event detected" ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] quirky multiple inheritance example!?
Hi,
I ran across a strange problem using mulitple inheritance that I hope someone can explain. Basically, I am implementing a Publisher pattern, and when I try to add threading, the order I list Base classes matters! Here is the short sample code-- all help explaining this is appreciated!
Thanks,
Marcus
---
import threading
class Publisher(object):
def __init__(self): self.listeners = {}
def register(self, id, object):
self.listeners[id] = self.listeners.get(id, object)
# This FAILS with AttributeError: 'FancyPublisher'
# object has no attribute 'listeners'
class FancyPublisher(threading.Thread, Publisher):
def __init__(self):
super(FancyPublisher, self).__init__()
F = FancyPublisher()
F.register('me', None)
# However, this succeeds!?
class FancyPublisher(Publisher, threading.Thread):
def __init__(self):
super(FancyPublisher, self).__init__()
F = FancyPublisher()
F.register('me', None)
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[Tutor] quickie: a better dynamic dictionary update?
Hi,I need to keep an updated dictionary of pictures in my application. I have a function which takes snapshots of the current pictures available. Some of the pictures in my dictionary have been deleted, so their dict entry needs to be removed. Here is a snippet of very ugly code I have which works. I'm looking for quick suggestions for a better implementation-- all nice replies welcomed! Thanks,Marcus-- code snippet# 1st, find the 'stale' items in our dictionary to delete# lstKeepers is a list of current pictures# Note: if I try to iterate over the keys of the dict and # remove-as-I-go, I get an exception (dict size changed# during iteration)lstRemove = []for key in myDict: if key not in lstKeepers: lstRemove.append(key) # 2nd, remove themfor oldKey in lstRemove: del myDict[oldKey] ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] custom container subclassing list-- slices are lists!?
Hi,I'd like to sublcass the built-in list type to create my own container. How can I make slices of the list be of type myclass-- currently they are lists. Example:>>> class MyFoo(list): def __init__(self, inlist): self = inlist[:]>>> me = MyFoo(range(10))>>> type(me)>>> type(me[0:3])All help appreciated! Thanks,Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] custom container subclassing list-- slices are lists!?
On 8/21/06, Marcus Goldfish <[EMAIL PROTECTED]> wrote: I'd like to sublcass the built-in list type to create my own container. How can I make slices of the list be of type myclass-- currently they are lists. Example:>>> class MyFoo(list): def __init__(self, inlist): self = inlist[:]>>> me = MyFoo(range(10))>>> type(me)>>> type(me[0:3]) First, a better example class:class MyFoo(list): def __init__(self, inlist): list.__init__(self, inlist)Second, I think I found a partial answer in the Feb 22, 2005 tutor thread http://aspn.activestate.com/ASPN/Mail/Message/python-tutor/2502290. To preserve type, I need to override some special functions. In the case of slicing, I need to override with something like this:def __getslice__(self, i, j): return MyFoo(list.__getslice__(self, i, j))This seems straightforward, but raises other questions: what other functions should I override, e.g., __add__, __radd__? Is there a preferred pythonic way to creating a custom list container? Finally, should I slice-copy my input list, inlist, to prevent side effects, or is this handled by list?Thanks,Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] __init__.py for running a file from commandline?
Hoping someone can help with this...I have a logical python namespace using a directory tree and __init__.py files. For example, PYTHONPATH points to ~pyroot, and I have the following:~pyroot/~pyroot/utils/ ~pyroot/utils/commands/mygrep.pyWhich makes it nice to code:# some python scriptimport utils.commands.mygrep as grepHowever, I have a problem when running python scripts from the command line. I would like to do this: > python utils.commands.mygrep.pybut it doesn't work. Is there a trick, or something that I am missing, that will let me run scripts like that?Thanks! Marcusps-- WinXP, python 2.4 ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] __init__.py for running a file from commandline?
On 11/11/06, Kent Johnson <[EMAIL PROTECTED]> wrote: Marcus Goldfish wrote: > Hoping someone can help with this... > > I have a logical python namespace using a directory tree and __init__.py > files. For example, PYTHONPATH points to ~pyroot, and I have the following: > > ~pyroot/ > ~pyroot/utils/ > ~pyroot/utils/commands/mygrep.py > > Which makes it nice to code: > > # some python script > import utils.commands.mygrep as grep > > However, I have a problem when running python scripts from the command > line. I would like to do this: > > > python utils.commands.mygrep.py > > but it doesn't work. Is there a trick, or something that I am missing, > that will let me run scripts like that? python utils/commands/mygrep.py will work if mygrep.py doesn't import other modules from utils; not sure if it will work with imports. Kent Kent, Hmmm... I tried this on my WinXP box-- didn't work nor with backslashing). I checked my environment variables in my shell, and PYTHONPATH points to ~pyroot. Am I missing something? Could this be a 'nix thing? Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] __init__.py for running a file from commandline?
On 11/27/06, Michael P. Reilly <[EMAIL PROTECTED]> wrote: When you type something from the command-line, you are at the whims of the WinXP command shell. You have to follow its rules, not Python's. It would need to have "python" in %PATH%, and then it would need to have to run "python C:\path\to\pyroot\utils\commands\mygrep.py". The arguments are determined before Python is even started, and they are parsed by the WinXP DOS-a-like shell. (Also why you cannot have ".", only Python understands dots). Doesn't python receive the command line argument, path-to-script in this case, for its own use and parsing? It seems like the solution I really seek is a command line switch that tells python that I am using namespace conventions, and that it should begin searching in the directory that PYTHONPATH points to. For example, c:> python -namespace utils.commands.mygrep.py Do either of you know of such a convenience? I suppose I could write a batch file, python.bat, that could implement this wrapping logic. Kent mentioned issues with importing modules, and those would still hold true since those are after Python starts. Also, the WinXP shell, does handle forward slashs, but you were probably not in the proper directory for the shell to find the file using "utils/commands/mygrep.py" pathname. Good spot-- forward slashes work, simply as relative path specifiers, so you have to be in the correct directory. I was not. Thus the problem. Also: it appears forward slashes only work as relative path specifiers (e.g., cd /temp), but fail if with a drive letter (e.g., c:/temp). Thanks guys. Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] curious struct problem
I'm trying to read a binary file using struct. This code works interactively in the IPython shell, but not as a function invoked from a command line (Windows). Can someone point out my error? Thanks! import struct def demux(filename, channel, nchannels): "Demultiplexes a stream of shorts (signed int16) from a file." fmt = str(nchannels) + 'h' sz = struct.calcsize(fmt) infile = open(fname, 'rb') chunk = infile.read(sz) while chunk: x = struct.unpack(fmt, chunk) chunk = infile.read(sz) infile.close() #struct.error: unpack str size does no match format ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] curious struct problem
On 2/2/07, Danny Yoo <[EMAIL PROTECTED]> wrote: > I'm trying to read a binary file using struct. This code works > interactively in the IPython shell, but not as a function invoked from a > command line (Windows). Can someone point out my error? Thanks! Hi Marcus, There is something very suspicious in the code. You don't happen to have any global variables in your program, do you? Let me underline what you might want to look at. > def demux(filename, channel, nchannels): Danny, Sorry, I had a typo. Attached below is the complete code actually copied from my editor. Notice that it doesn't do anything now, which is fine b.c. I just want to troubleshoot the problem. The error is reproduced as a comment below the source. As far as I know, there are no globals; I am invoking this from a command line prompt: python demux.py foo.bin 1 1 # --- import struct def demux(fname, ch=1, nchan=1): fmt = str(nchan) + 'h' # nchan of short (int16) blockSize = struct.calcsize(fmt) # file setup infile = open(fname, 'rb') #outfile = open(fname + 'ch' + str(ch), 'wb') # iterate over data chunk = infile.read(blockSize) while chunk: x = struct.unpack(fmt, chunk) chunk = infile.read(blockSize) # file cleanup # outfile.close() infile.close() # - # main() # - def main(argv=None): if argv is None: printHelp() demux(argv[1], int(argv[2]), int(argv[3])) # filename, ch, nchans if __name__ == "__main__": import sys sys.exit(main(sys.argv)) # C:\python\python demux.py demux.py 1 1 # Traceback (most recent call last): # File "demux.py", line xx, in ? # sys.exit(main(sys.argv)) # File "demux.py", line xx, in main # demux(argv[1], int(argv[2]), int(argv[3])) # filename, ch, nchans # File "demux.py", line xx, in demux # x = struct.unpack(fmt, chunk) # struct.error: unpack str size does not match format ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] curious struct problem
On 2/2/07, Danny Yoo <[EMAIL PROTECTED]> wrote: There is something very suspicious in the code. You don't happen to have any global variables in your program, do you? I think I found the problem: the last chunk read is incomplete, so there is size(chunk) is not sufficient to unpack according to the format string. Thanks! ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] class design - base classes with optional properties?
I'm trying to design a base class for a hierarchy. The properties I want to specify for the base class depend on the values of other properties of the base class. For instance, in this toy example of a base FoodProcessor class: class FoodProcessor: "Model for a kitchen appliance food processor" speed_settings # example [1, 2, 3, 4] blade_settings # example ["slice", "grate", "grind"] slice_thickness # example ["thin", "thick"], but only if blade_setting is "slice" it only make sense to have the slice_thickness property set when blade_settings = "slice"; otherwise, it would be preferable to only define the speed_settings and blade_settings properties. For example: class ProcessorA(FoodProcessor): "A slicing-only processor" speed_settings = [1, 2, 3, 4] blade_settings = "slice" slice_thickness = ["thin", "thick"] class ProcessorB(FoodProcessor): "A non-slicing processor" speed_settings = [1,2,3,4] blade_settings = ["grate", "grind"] slice_thickness = None Can anyone suggest some work-arounds, or refactoring for this type of design? Is there a design pattern for this? Thanks! Marcus ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
