Re: What is the purpose of "To bind the key M-DEL, use "\M\d", not M-DEL"

["Lennart Borgman (gmail)" <lennart.borgman@gmail.com>]

Andreas Schwab wrote:
> "Lennart Borgman (gmail)" <lennart.borgman@gmail.com> writes:
>
>   
>> Which actually works, yes. But isn't there a point in telling about
>> M-backspace instead since M-DEL is made in the platform specific
>> translation in function-key-map?
>>     
>
> No, M-DEL is the canonical key.  Anthing defined via function-key-map is
> non-canonical.
>   

Ah, thanks. That means my latest patch for the tutorial is wrong AFAICS 
now - so please do not install that - yet.

I had to consult Webster to see what canonical really means ....

Now let me see if I understand this... - here is then another question 
around this:

As I understand it now the preferable way to define a key is (of course) 
always to use a canonical representation. Maybe it even can not be done 
in any other way?

But then I do not understand the use of M-backspace. In pc-mode.el 
M-backspace is used for keybinding. Works ok on w32 and I guess on other 
platforms too? But backward-kill-word is not bound to M-backspace 
directly on w32, but instead through function-key-map. Why is it so? 
Where is backward-kill-word on other systems? What does C-h w give? What 
does M-backspace do on other systems?