[XeTeX] Greek letterspacing with soul

[Ulrike Fischer]

Am Tue, 25 May 2010 18:17:09 +0200 schrieb Pablo Rodríguez:

> On 05/25/2010 05:28 PM, Ulrike Fischer wrote:
>> Am Tue, 25 May 2010 17:12:08 +0200 schrieb Pablo Rodríguez:
>>
>>>   (I know that \makeatletter ends with \makeatother,
>>> although I'm not sure what are they used for ;-).)
>>
>> Well \makeatletter makes @ (at) to a letter, which means that you
>> can use commands with @ in their names (command names end at the
>> first non-letter char), \makeatother makes @ to a "non-letter".
> 
> Thanks for your clear explanation, Ulrike.
> 
> But naming commands with @ is only a convention, isn't it?

It shows that a command is an internal command and that "the normal
user" should be careful (and need to know how to make @ to a letter)
before redefining it. 

The latex3 code use : and _ as "letters" for the same purpose: e.g. 
"\msg_kernel_new:nnnn" is a latex3 command.


-- 
Ulrike Fischer