Tkinter __call__

[Gigs_]

James Stroud wrote:
> Gigs_ wrote:
>> from Tkinter import *
>> from tkFileDialog   import askopenfilename
>> from tkColorChooser import askcolor
>> from tkMessageBox   import askquestion, showerror
>> from tkSimpleDialog import askfloat
>>
>> demos = {
>>     'Open':  askopenfilename,
>>     'Color': askcolor,
>>     'Query': lambda: askquestion('Warning', 'You typed          
>> "..."\nConfirm?'),
>>     'Error': lambda: showerror('Error!', "He's dead, Jim"),
>>     'Input': lambda: askfloat('Entry', 'Enter credit card number')
>> }
>>
>>
>> class Demo(Frame):
>>     def __init__(self, parent=None):
>>         Frame.__init__(self, parent)
>>         self.pack()
>>         Label(self, text="Basic demos").pack()
>>         for (key, value) in demos.items():
>>             func = (lambda key=key: self.printit(key))
>>             Button(self, text=key, command=func).pack(side=TOP, 
>> fill=BOTH)
>>     def printit(self, name):
>>         print name, 'returns =>', demos[name]()
>>
>>
>> I have tried but cant get it to work properly.
>> I want to instead printit method to put __call__ and call it like that
>> Can someone help me, please?
> 
> The code you have should work. My guess is that you don't understand 
> lambda and so you want to do it a "different" way, using a "callable"? 
> Well, that's what lambda does, it makes a callable object:
> 
> 
> Python 2.5 (r25:51918, Sep 19 2006, 08:49:13)
> [GCC 4.0.1 (Apple Computer, Inc. build 5341)] on darwin
> Type "help", "copyright", "credits" or "license" for more information.
> py> key = 1
> py> callable(lambda key=key: self.printit(key))
> True
> py> '__call__' in dir(lambda key=key: self.printit(key))
> True
> 
> 
> 
> So the code you have already does what you want to do. Maybe understand 
> what you are studying before you reinvent the wheel--you will save 
> yourself a lot of frustration.
> 
> James
I understand lambda, and I know that code is working. But want to do for 
exercise with __call__. This coed is from programming python 2ed boo