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Dear XeTeX fidels,<BR>
<BR>
In my first document written with XeTeX, I wanted to do an alias for the abbreviation CO_2 (carbon dioxyde), but had two difficulties.<BR>
<BR>
My first one was to try to use something like this : %\newcommand{\co2}{CO$_2$}<BR>
The problem was that it seems we cannot use "numbers" in the command name, such as the '2' in \co2. Is there a way to circumvent this?<BR>
<BR>
Another weird issue I ran into was, after changing \co2 to something more wordy as \codeux, my actual replacement would delete all trailing space. Let me explain by an example : <BR>
ex : The traffic in developed nations is the cause to an average of 26% of the \codeux emissions. <BR>
<BR>
Results : The traffic in developed nations is the cause to an average of 26% of the CO_2emissions.<BR>
<BR>
Note the lack of a space character between the _2 subscript and emissions. Using CO$_2$ straight in my text solved the problem, surprisingly. Is there an explanation for this? What should I do to prevent this from happening? <BR>
<BR>
Cheers.
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