Newbie needs "interface"

[Fredrik Lundh]

Roberto Bonato wrote:
>         I'm writing a function that implements an algorithm and that
> prints intermediate results all along the (usually very long)
> computation. Sometimes I want the results to be written on the stdout,
> sometimes on a Tkinter Text widget, sometimes to a file. I feel the need
> of something like a Java Interface with a method "write" to wrap all
> such devices into.

in python, interfaces are informal, so all you have to do is to
create something with a "write" method.  for example:

import Tkinter

class TextWithWrite(Tkinter.Text):
    def write(self, string):
        self.insert(Tkinter.END, string)
        self.see(Tkinter.END)
        self.update_idletasks() # redraw me

if print_to_file:
    outfile = open(myfile, "w")
else:
    w = TextWithWrite(master)
    w.pack()
    outfile = w

print >>outfile, "something"
print >>outfile, "something else"

</F>

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