On 05/02/2012 18:01, Bruno Le Floch wrote:
> \regex_const:Nn \recurrence_tl_integer_regex { ^[-+]*[0-9]+$ }
>   % => \l_recurrence_integer_regex
> \regex_const:Nn \recurrence_tl_true          { true }
>   % => \l_recurrence_true_regex

Constants => \c_...
-- 
Joseph Wright