On 24/10/2008, at 7:13 PM, Morten Høgholm wrote:
>
> It is used in a few cases such as
>
> \def_long:Npn \tlp_if_in:NnTF #1#2{
>  \def_long:Npn\tmp:w ##1 #2 ##2\q_stop{
>    \quark_if_no_value:nFT{##2}
>  }
>  \exp_after:NN \tmp:w #1 #2 \q_no_value \q_stop
> }
>
> If there was no FT variant, this function would either have to read
> the TF arguments twice or the quark test would have to be done
> manually.
>
> The FT variant was never meant to be heavily used - just a shuffle
> variant so to speak.

Oh, yes, I remember seeing a couple of cases like that. And then  
promptly forgot about them :(

I'll write a bit of documentation explaining the whole thing, then --  
something along the lines of

   "The "FT" variant is only intended for reversing
    conditionals that are passed internally; it is
    highly recommended against using them in explicit
    branching code."

W