Will Robertson a écrit :
> So here, while \the isn't a macro, it will expand when used correctly in
> an edef (e.g., \edef\foo{\the\baselineskip} ).  I've explicitly caught
> undefined macros to return "F" because it just seemed more logical that
> way.
In my understanding of the term, macros are always "expandable". I think
in the context of this function, "expandable" should mean the same as in
the TeXbook, (p. 212-214 in my edition) after the text

> Now let's consider the control sequences that are expanded whenever
> expansion has not been inhibited. Such control sequences fall into
> several classes:

Here macros are described as "expandable" regardless of whether they are
defined or not.