[XeTeX] Whitespace in input

[Philip TAYLOR]

Arthur Reutenauer wrote:
> On Tue, Nov 15, 2011 at 02:20:17PM +0000, Philip TAYLOR wrote:
>> No ! "A catcode is for life, not just for Christmas" !  Once a
>> character has been read, and bound into a character/catcode pair,
>> that catcode remains immutable.
>
>    Do you mean that as a general good practice in TeX programming, or as
> a description of how TeX works?  The latter is obviously wrong.

"The latter" is what the TeXbok says (P.~39) : "Once a category code
has been attached to a character token, the attachment is permanent."

** Phil.