Hello, I was reading through part of l3tlp, and I came across: \def_long_test_function:npn{tlist_if_eq:nn}#1#2{ \tlp_set:Nx \l_testa_tlp {\exp_not:n{#1}} \tlp_set:Nx \l_testb_tlp {\exp_not:n{#2}} \if_meaning:NN\l_testa_tlp \l_testb_tlp } Why is this \tlp_set:Nx plus \exp_not:n, rather than just \tlp_set:Nn? I assume I'm missing some complex edge case. -- Joseph Wright