Morten Høgholm wrote:

>> \toks_set:No \l_tmpa_toks {stuff including "#1"}
> \toks_set:Nn I think you mean.

Yes, of course.

>> \tlp_set:Nx \l_my_tlp {\toks_use:N\l_tmpa_toks}
>> Is there a pre-coded function for this (I may have misunderstood somewhere).
> Not exactly precoded but what you usually do is
>   \tlp_set:Nx \l_my_tlp {\exp_not:n{unexpanded #1}}

Ah yes, that works nicely.

> The at first sight weird looking \exp_not:o and \exp_not:f start
> becoming more useful in this context.

I'll take your word for it!
Joseph Wright