With my MacBook, on IDLE application, I can't type any character like this 
one \.

\ works fine for me and I suspect almost everyone else.
Please bring this up on comp.lang.python or python-list or
gmane.comp.python.general to see if any other Macbook users have this
problems or any ideas on what might be wrong with your particular
installation.

@ Terry J. Reedy

If it is working for you it doesn't necessarily mean that it is working
for mankind in general.

I traced down the problem to the OS X- implementation of Idle in general
and submitted an inquiry to the general python list as you suggested.
The feedback was null- nada- niente. But in the meantime I received a
nice bunch of Spam instead.

http://mail.python.org/pipermail/python-list/2008-August/504330.html

I believe the original poster has a French keyboard and seems to have 
similar problems. The problem is that Idle seems to ignore the
international local keyboard setting. And as we do have two significant
letters ("#" and "'") at the keyboard position where you have the "\"
Idle seems to filter the entry of a backslash.

@ marc 67
HTH

Cheers
Ulf

Can you verify if it is possible to type '\' in a standard Tkinter.Text ?

Same probleme here with Idle 2.6.2, with a french keyboard.
I finally thought that it was due to a default binding recorded as 
<Option><Slash> or <Option><Shift>:, something like that, which is 
identical to the binding of Backslash character on my keyboard.
So I modified the binding "expand word" (can't remember why this one), 
recorded it under a new key set and applied it. After that, the 
backslash combination worked perfectly!!

But ... the bug now is that if I come back to the default OSX key set, 
it still works ...

(Another detail is that with the Logitech keyboard configuration (usb PC 
keyboard), it works at first try...)

Maybe this workaround will save your afternoon ...

I have the same problem with a danish keyboard and OSX snowleopard..
I can use \ in both the command editor and pretty everywhere else but not in Idle.

Do I understand it correctly when I write that you normally use "Option+Slash" to enter a backslash on your keyboard?

That would explain why updating the keyboard bindings makes it possible to type a backslash.

I'm not sure how we could fix this issue in a way that wouldn't break existing bindings for folks with an english keyboard (as just updating the default keybindings would likely upset those people).

Yes, that is correct .

Well, thanks for replying, anyway. I guess I'll have to use linux instead.

On Sun, Mar 13, 2011 at 12:00 AM, Ronald Oussoren <report@bugs.python.org>wrote:

>
> Ronald Oussoren <ronaldoussoren@mac.com> added the comment:
>
> Do I understand it correctly when I write that you normally use
> "Option+Slash" to enter a backslash on your keyboard?
>
> That would explain why updating the keyboard bindings makes it possible to
> type a backslash.
>
> I'm not sure how we could fix this issue in a way that wouldn't break
> existing bindings for folks with an english keyboard (as just updating the
> default keybindings would likely upset those people).
>
> ----------
>
> _______________________________________
> Python tracker <report@bugs.python.org>
> <http://bugs.python.org/issue3493>
> _______________________________________
>