[latex3-commits] [latex3/latex3] main: Mumble (a1a48690e)

[Joseph Wright]

On 01/11/2023 16:25, Frank Mittelbach wrote:
>>       \__kernel_tl_set:Ne #5 { \exp_not:o \l_@@_unused_clist }
>> -    \__kernel_tl_set:Nn \l_@@_unused_clist {#1}
>> +    \__kernel_tl_set:Ne \l_@@_unused_clist { \exp_not:n {#1} }
>>     }
> 
> what am I missing here? I would have thought this makes zero differences 
> other than being slower
> 
> ehh wait, is this to do with #1 perhaps containing # marks?

We had \tl_set:Nn here, but as pointed out in the linked issue, this is 
a bit poor as it's a clist. Here, we don't really want to have to do 
clist processing as #1 is already a clist we've pushed onto the input 
stack. So I decided to go with \__kernel... But i forgot that there is 
no \__kernel_tl_set:Nn, only \__kernel_tl_set:Ne. Doing

      \__kernel_tl_set:Ne \l_@@_unused_clist { \exp_not:n {#1} }

is what \tl_set:Nn does but without any checking, so it's no worse than 
the older code and in a checking context will be faster.

Joseph