> The is no pre-build 'strip_braces' function at present. You don't say if > we are talking one set of braces or multiple sets. For the former case, > a simple 'do nothing' loops would be easiest: > > \tl_set:Nx \l_temp_tl > { \tl_map_function:NN \l_temp_tl \exp_not:n } Agreed with Joseph. If you need to recursively remove braces, and don't care about speed, the following should work (unless I screwed up), and it doesn't remove spaces, although it easily could. \cs_new:Npn \tl_ungroup_all:n { \tex_romannumeral:D \tl_act_aux:NNNnn \tl_act_ungroup_normal:nN \tl_act_ungroup_group:nn \tl_act_ungroup_space:n { } } \cs_new:Npn \tl_act_ungroup_space:n #1 { \tl_act_output:n {~} } \cs_new:Npn \tl_act_ungroup_normal:nN #1 #2 { \tl_act_output:n {#2} } \cs_new:Npn \tl_act_ungroup_group:nn #1 { \tl_act_group_recurse:Nnn \tl_act_output:n { \tl_ungroup_all:n } } Cheers, Bruno