%%% Double-circumflex trap

Is there a difference between those two cases?

\beginverbatim
\number`\^^A
\number`^^A
\endverbatim

And how about this?

\beginverbatim
\number`\^^@
\number`^^@
\endverbatim

In the case of \verb'^^A' (character code 1), both lines yield the number 1, 
the backslash character's presence before the double-circumflex doesn't 
influence the result. In the second case, the first line yields 0, while the 
second results in 32. The reason is that the character of the code 0 
(\verb'^^@') has the associated category code `ignored' (9). Any character of 
the category 9 will simply be omitted, except when there is a backslash 
immediately before it. If there is no backslash, the very next character is 
considered, which is a code 32\dots Well, actually its end-line character, 
which is replaced by the character of the code being a current value of 
\verb'\endlinechar', which is 13 by default, and character 13 has a default 
category code 5, which is finally converted to the character 32.

\endinput
