erw-l3 (4jun20)

git-svn-id: svn://tug.org/texlive/trunk@55414 c570f23f-e606-0410-a88d-b1316a301751

1 files changed, 377 insertions, 265 deletions

diff --git a/Master/texmf-dist/tex/latex/erw-l3/erw-l3.sty b/Master/texmf-dist/tex/latex/erw-l3/erw-l3.sty
index ba4182d0e1d..18e94e85057 100644
--- a/Master/texmf-dist/tex/latex/erw-l3/erw-l3.sty
+++ b/Master/texmf-dist/tex/latex/erw-l3/erw-l3.sty
@@ -5,385 +5,499 @@
 %% The original source files were:
 %%
 %% erw-l3.dtx  (with options: `package')
-%% ----------------------------------------------------------------
-%% erw-l3 Utilities built around expl3
+%% ----------------------------------------------------------------------------
+%% erw-l3 --- Utilities for LaTeX3 programming
 %% Released under the LaTeX Project Public License v1.3c or later
 %% See http://www.latex-project.org/lppl.txt
-%% ----------------------------------------------------------------
+%% ----------------------------------------------------------------------------
 %% 
-\RequirePackage{expl3}[2018/06/01]
-\RequirePackage{xparse}[2018/02/01]
-\RequirePackage{l3keys2e}
-\ProvidesExplPackage
-  {erw-l3}                            % Package name
-  {2020/02/05}                        % Release date
-  {0.1.6}                             % Release version
-  {Utilities built around expl3}      % Description
-\NeedsTeXFormat{LaTeX2e}
-\ExplSyntaxOn
-\msg_new:nnn{erw}{generic}{#1}
-\cs_set:Npn \erw_compose:NnV
-  #1 % method
-  #2 % funs
-  #3 % var
-{
-  \erw_fold_set_par:n{Nf}
-  \erw_fold_apply_par:n{Nf}
-  \erw_cs_set_inline:Nn \__erw_map:n
+ \NeedsTeXFormat{LaTeX2e}[2020/02/02]
+ \RequirePackage{etoolbox}[2019/09/21]
+ \RequirePackage{l3keys2e}[2020/03/06]
+ \RequirePackage{xparse}[2020/03/06]
+ \ProvidesExplPackage
+ {erw-l3}                                                                            % Package name
+ {2020/06/04}                                                                        % Release date
+ {3.1}                                                                               % Release version
+ {erw-l3 --- Utilities for LaTeX3 programming }                                      % Description
+\cs_new:Nn \__erw_cs_name:N
+{
+  \exp_last_unbraced:Nf \use_i:nnn {\cs_split_function:N #1}
+}
+\cs_new:Nn \erw_cs_compose:NnN
+{
+  \erw_cs_set_inline:Nn \g__erw_tl_function:n
   {
-     #1{##1}#3
+    #1{##1}#3
   }
-  \exp_args:Nf\erw_map:n
+  \exp_args:Nf\erw_tl_map:n
   {
-      \tl_reverse:n{#2}
+    \tl_reverse:n{#2}
   }
 }
-\cs_set:Npn \erw_compose:nV #1 #2
+\cs_set:Npn \erw_cs_identity:n #1{#1}
+\cs_new_protected:Nn \erw_cs_set_inline:Nn
 {
-  \erw_compose:NnV \erw_fold:NV {#1} #2
+  \cs_set:Npn #1 ##1{#2}
 }
-\cs_set:Npn \erw_compose_c:nV #1 #2
+\cs_generate_variant:Nn \erw_cs_set_inline:Nn {cn}
+\cs_new:Nn \erw_cs_gset_inline:Nn
 {
-  \erw_compose:NnV \erw_fold:cV {#1} #2
+  \cs_gset:Npn #1 ##1{#2}
 }
-\tl_new:N \__erw_compose_tl
-\cs_set:Npn \erw_compose:nn #1 #2
+\cs_generate_variant:Nn \erw_cs_gset_inline:Nn {cn}
+\int_new:N \g__erw_csint_int
+\cs_new:Nn \__erw_csint_name: {\erw_csint_name:n{\g__erw_csint_int}}
+\cs_new:Nn \erw_csint:nn
 {
-  \tl_set:Nn \__erw_compose_tl {#2}
-  \erw_compose:nV{#1}\__erw_compose_tl
-  \__erw_compose_tl
+ \exp_args:No \use:c{\erw_csint_name:n{#1}}{#2}
 }
-\cs_set:Npn \erw_compose_c:nn #1 #2
+\cs_new:Nn \erw_csint_name:n {__erw_csint_\int_to_alph:n{#1}:n}
+\cs_new_protected:Nn \erw_csint_new:n
 {
-  \tl_set:Nn \__erw_compose_tl {#2}
-  \erw_compose_c:nV{#1}\__erw_compose_tl
-  \__erw_compose_tl
+  \int_incr:N \g__erw_csint_int
+  \exp_args:No
+  \erw_cs_set_inline:cn{\__erw_csint_name:}
+  {
+    \token_if_cs:NTF
+    {#1}
+    {#1{##1}}
+    {#1}
+  }
 }
-\cs_set:Npn \erw_compose_seq:nV #1 #2
+\cs_new:Nn \erw_csint_names_braced:nnn
 {
-  \erw_compose:NnV \erw_fold_seq:NV {#1} #2
+  \int_step_function:nnnN { #1 }{ #2 }{ #3 } \erw_csint_names_braced:n
+  % TODO \tl_range_braced:nnn?
 }
-\cs_set:Npn \erw_compose_seq_c:nV
-  #1 % funs
-  #2 % seq
+\cs_new:Nn \erw_csint_names_braced:n {{\erw_csint_name:n{#1}}}
+\cs_new:Nn \erw_csint_names_braced:
 {
-  \erw_compose:NnV \erw_fold_seq:cV {#1} #2
+  \erw_csint_names_braced:nnn{1}{1}{\g__erw_csint_int}
 }
-\cs_set:Npn \erw_compose_vers:nV #1 #2
+\cs_new_protected:Nn \erw_csint_reset:
 {
-   \msg_error:nnn{erw}{generic}{erw_compose_vers:nV~yet-to~be~implemented}
+  \int_zero:N \g__erw_csint_int
+  \tl_set:Nn \__erw_csint_ext_tl{}%^^A TODO remove?
 }
-\cs_set:Npn \erw_compose_seq_vers:nV #1 #2
+\cs_set:Npn \__erw_int_range:nnn #1 #2 #3
 {
-   \msg_error:nnn{erw}{generic}{erw_compose_vers:nV~yet-to~be~implemented}
+  \int_compare:nNnTF
+  {
+    \int_eval:n{#2+1}
+  }>{#3}
+  {
+    {#1}
+  }
+  {
+    \__erw_int_range:nnn
+    {
+      \exp_args:Nx\erw_tl_append_item:nn{#1}
+      {
+        \int_eval:n{#2+1}
+      }
+    }
+    {\int_eval:n{#2+1}}
+    {#3}
+  }
 }
-\cs_set:Npn \erw_compose_vers:nn #1 #2
+\cs_new:Nn \erw_int_range:nn
 {
-   \erw_numbrd_cs_reset:{}
-      \tl_map_function:nN{#1}\erw_numbrd_cs_new:n
-      \exp_last_unbraced:Nx
-      \erw_compose_c:nn
-         {{\erw_numbrd_cs_names_braced:{}}}
-         {#2}
+  \__erw_int_range:nnn {{#1}}{#1}{#2}
 }
-\cs_set:Npn \erw_accum:nn #1 #2
+\cs_new:Nn \erw_int_range:n
 {
-    {#1{#2}}
+  \__erw_int_range:nnn {}{0}{#1}
 }
-\cs_set:Npn \__erw_cs_name:N #1
+\cs_new:Nn \erw_keyval_error:Nn{\msg_error:nnnnn{__erw}{keyval/n}{\erw_keyval_error:Nn}{#1}{#2}}
+\cs_new:Nn \erw_keyval_error:Nnn{\msg_error:nnnnnn{__erw}{keyval/nn}{\erw_keyval_error:Nnn}{#1}{#2}{#3}}
+\cs_new_protected:Nn\erw_keyval_parse:NNNn
 {
-    \exp_last_unbraced:Nf \use_i:nnn {\cs_split_function:N #1}
+  \cs_set_protected:Nn \__erw_keyval_function:n {#2 #1{##1}}
+  \cs_set_protected:Nn \__erw_keyval_function:nn {#3 #1{##1}{##2}}
+  \keyval_parse:NNn
+  \__erw_keyval_function:n
+  \__erw_keyval_function:nn
+  {#4}
 }
-\cs_set:Npn \erw_apply:Nn
-  #1 % fun
-  #2 % tl
+\cs_new_protected:Npn \erw_lambda:nnn #1 #2 #3
 {
-  #1{#2}
+  \exp_args:NNx
+  #1 \__erw_lambda_expression
+  {#2}
+  {#3}
+  \__erw_lambda_expression
 }
-\cs_generate_variant:Nn \erw_apply:Nn {No, Nf, Nx, c}
-\cs_set:Npn \erw_cs_set_eq:NN #1 #2
+\msg_new:nnn{__erw}{generic}{#1}
+\msg_new:nnn{__erw}{keyval/nn}{#1#2{#3}{#4};~encountered~key=val~where~only~key~required}
+\msg_new:nnn{__erw}{keyval/n}{#1#2{#3};~encountered~key~~where~only~key=val~required}
+\msg_new:nnn{__erw}{separ}{#1~expects~1~to~3~items,~#2}
+\msg_new:nnn{__erw}{timestamp / base}{Calling~#1,~arg~must~be~'dec|hex'}
+\msg_new:nnn{__erw}{timestamp / period}{Calling~#1,~arg~must~be~'date|time|datetime'}
+\msg_new:nnn{erw}{notset}{#1~not~set}
+\cs_new_protected:Nn \__erw_prop_map_item:NNN
 {
-  \cs_set:Npn #1 ##1{#2{##1}}
+  \cs_set_protected:Nn \__erw_function:nn
+  {
+    #1 #2 {##1}{##2}
+  }
+  \prop_map_function:NN #3 \__erw_function:nn
 }
-\cs_generate_variant:Nn \erw_cs_set_eq:NN {cN}
-\cs_set:Npn \erw_cs_gset_eq:NN #1 #2
+\cs_new_protected:Nn \erw_prop_to_clist:Nn
 {
-  \cs_gset:Npn #1 ##1{#2{##1}}
+  \cs_set:Nn \__erw_keyval_function:n {,\prop_item:Nn#1{##1}}
+  \exp_args:Nf
+  \tl_tail:n
+  {
+    \keyval_parse:NNn
+    \__erw_keyval_function:n
+    \erw_keyval_error:Nnn
+    {#2}
+  }
 }
-\cs_generate_variant:Nn \erw_cs_gset_eq:NN {cN}
-\cs_set:Npn \erw_cs_set_inline:Nn #1 #2
+\cs_generate_variant:Nn \erw_prop_to_clist:Nn { c }
+\cs_new_protected:Nn \erw_prop_map_item:NNN
 {
-  \cs_set:Npn #1 ##1{#2}
+  \prop_if_exist:NTF #2
+  {\__erw_prop_map_item:NNN #1#2#3}
+  {
+    \prop_new:N #2
+    \erw_prop_map_item:NNN #1#2#3
+  }
 }
-\cs_generate_variant:Nn \erw_cs_set_inline:Nn {cn}
-\cs_set:Npn \erw_cs_gset_inline:Nn #1 #2
+\cs_new_protected:Nn\erw_prop_keyval_parse:NNNn
 {
-  \cs_gset:Npn #1 ##1{#2}
+  \prop_if_exist:NTF#1
+  {\erw_keyval_parse:NNNn #1#2#3{#4}}
+  {
+    \prop_new:N #1
+    \erw_prop_keyval_parse:NNNn#1#2#3{#4}
+  }
 }
-\cs_generate_variant:Nn \erw_cs_gset_inline:Nn {cn}
-\tl_set:Nn \__erw_fold_set_par_tl{\c_novalue_tl}
-\tl_set:Nn \__erw_fold_apply_par_tl{\c_novalue_tl}
-\cs_set:Npn \erw_fold_set_par:n #1
+\keys_define:nn{__erw}
 {
-  \tl_set:Nn \__erw_fold_set_par_tl{#1}
+  tl/fold_set_par.tl_gset:N = \g__erw_tl_fold_set_par_tl,
+  tl/fold_set_par.value_required:n = true,
+  tl/fold_set_par.default:n = {Nf},
+  tl/fold_set_par.initial:n = {Nf},
+  tl/fold_apply_par.tl_gset:N = \g__erw_tl_fold_apply_par_tl,
+  tl/fold_apply_par.value_required:n = true,
+  tl/fold_apply_par.default:n = {Nf},
+  tl/fold_apply_par.initial:n = {Nf}
 }
-\cs_set:Npn \erw_fold_apply_par:n #1
+\cs_new_protected:Nn\erw_option:n
 {
-  \tl_set:Nn \__erw_fold_apply_par_tl{#1}
+  \keys_set:nn{__erw}{#1}
 }
-\cs_set:Npn \erw_fold:NV
-  #1 % fun
-  #2 % var
+\tl_new:N \g__erw_seq_fold_item_tl
+\cs_new_protected:Nn\__erw_seq_put_right_clist:Nn
 {
-  \use:c{tl_set:\__erw_fold_set_par_tl}
-     #2
-    {\use:c{erw_apply:\__erw_fold_apply_par_tl}{#1}{#2}}
+  \cs_set_protected:Nn \__erw_function:n
+  {
+    \seq_put_right:Nn #1{##1}
+  }
+  \keyval_parse:NNn
+  \__erw_function:n
+  \erw_keyval_keyonly:nn
+  {#2}
 }
-\cs_generate_variant:Nn \erw_fold:NV {cV}
-\tl_new:N \__erw_fold_seq_item_tl
-\cs_set:Npn \erw_fold_seq:NV
-  #1 % fun
-  #2 % seq
+\cs_generate_variant:Nn \__erw_seq_put_right_clist:Nn { c }
+\cs_new_protected:Nn\__erw_seq_put_right_prop:NNn
 {
-  \seq_get_right:NN #2 \__erw_fold_seq_item_tl
-  \erw_fold:NV #1 \__erw_fold_seq_item_tl
-  \seq_put_right:No #2 {\__erw_fold_seq_item_tl}
+  \__erw_seq_put_right_clist:Nn #1
+  {\erw_prop_to_clist:Nn #2 {#3}}
 }
-\cs_generate_variant:Nn \erw_fold_seq:NV {cV}
-\cs_set:Npn \erw_identity:n #1{#1}
-\prg_set_conditional:Npnn \erw_is_matrix:n #1 { p, TF }
+\cs_generate_variant:Nn \__erw_seq_put_right_prop:NNn { cc }
+\cs_new_protected:Nn\erw_seq_put_right_clist:Nn
 {
-    \erw_gset_map_inline:n{==\tl_count:n{##1}}
-    \int_compare:nTF
-    {
-        \exp_args:Nf\tl_count:n{\tl_head:n{#1}}
-        \exp_args:Nf \erw_map:n
-        {
-                \tl_tail:n{#1}
-            }
-    }
-    {\prg_return_true:}
-    {\prg_return_false:}
+  \seq_if_exist:NTF#1
+  {\__erw_seq_put_right_clist:Nn#1{#2}}
+  {\seq_new:N#1\erw_seq_put_right_clist:Nn#1{#2}}
 }
-\cs_set:Npn \erw_last_item:n #1
+\cs_generate_variant:Nn \erw_seq_put_right_clist:Nn { c }
+\cs_new_protected:Nn\erw_seq_put_right_prop:NNn
 {
-    \exp_args:Nof \tl_item:nn
-        {#1}
-        {
-            \tl_count:n{#1}
-        }
+  \seq_if_exist:NTF#1
+  {\__erw_seq_put_right_prop:NNn#1#2{#3}}
+  {\seq_new:N#1\erw_seq_put_right_prop:NNn#1#2{#3}}
 }
-\cs_set:Npn \erw_merge:nn #1 #2
+\cs_generate_variant:Nn \erw_seq_put_right_prop:NNn { cc }
+\cs_new_protected:Nn \erw_seq_fold:NN
 {
-    {#1#2}
+  \seq_get_right:NN #2 \g__erw_seq_fold_item_tl
+  \erw_tl_fold:NN #1 \g__erw_seq_fold_item_tl
+  \seq_put_right:No #2 {\g__erw_seq_fold_item_tl}
 }
-\cs_set:Npn \erw_repeat:nn #1 #2
+\cs_generate_variant:Nn \erw_seq_fold:NN {cN}
+\cs_new:Nn \erw_seq_use:Nn
 {
-    \int_step_inline:nnnn{1}{1}{#1}{#2}
+  \exp_last_unbraced:NNf
+  \seq_use:Nnnn #1
+  \erw_tl_separators:n{#2}
 }
-\cs_set:Npn \erw_split:nnn #1 #2 #3
+\cs_new:Nn \__erw_sys_date_dec:
 {
-    \tl_head:n{#1}
-    \use:c{exp_args:#3} \tl_map_inline:nn
-    {
-        \tl_tail:n
-        {
-            #1
-        }
-    }{#2##1}
+  \int_eval:n
+  {
+    \c_sys_year_int * 10000
+    +\c_sys_month_int * 100
+    +\c_sys_day_int *  1
+  }
 }
-\cs_set:Npn \erw_split:nn #1 #2
+\cs_new:Nn \__erw_sys_date:N{\int_to_hex:n{\__erw_sys_date_dec:}}
+\cs_new:Nn \__erw_sys_date_hex:{\int_to_hex:n{\__erw_sys_date_dec:}}
+\cs_new:Nn \__erw_sys_time_dec:
 {
-    \erw_split:nnn{#1}{#2}{Nf}
+  \int_eval:n
+  {
+    \c_sys_hour_int * 100
+    +\c_sys_minute_int * 1
+  }
 }
-\cs_set:Npn \__erw_int_range:nnn #1 #2 #3
+\cs_new:Nn\__erw_sys_time_hex:{\int_to_hex:n{\__erw_sys_time_dec:}}
+\cs_new:Nn\__erw_sys_datetime_base:n
 {
-    \int_compare:nNnTF
-    {
-            \int_eval:n{#2+1}
-    }>{#3}
-    {
-        {#1}
-    }
-    {
-        \__erw_int_range:nnn
-        {
-            \exp_args:Nx\erw_accum:nn{#1}
-            {
-                \int_eval:n{#2+1}
-            }
-        }
-        {\int_eval:n{#2+1}}
-        {#3}
-    }
+  \int_case:nnTF{#1}
+  {
+    {10}{dec}
+    {16}{hex}
+  }
+  {\c_empty_tl}
+  {\msg_error:nnn{__erw}{timestamp / base}{\__erw_sys_datetime_base:n{#1}}}
 }
-\cs_set:Npn \erw_int_range:nn #1 #2
+\cs_new:Nn\__erw_sys_datetime_join:nn{\erw_tl_join:nnn{#1}{\g__erw_sys_timestamp_delim_str}{#2}}
+\cs_new:Nn\__erw_sys_datetime_period:n
 {
-    \__erw_int_range:nnn {{#1}}{#1}{#2}
+  \str_case:nnTF{#1}
+  {
+    {date}{date}
+    {time}{time}
+    {datetime}{datetime}
+  }
+  {\c_empty_tl}
+  {\msg_error:nnn{__erw}{ timestamp / period }{\__erw_sys_datetime_period:n{#1}}}
 }
-\cs_set:Npn \erw_int_range:n #1
+\cs_new:Nn\__erw_sys_datetime_dec: {\__erw_sys_datetime_join:nn{\__erw_sys_date_dec:}{\__erw_sys_time_dec:}}
+\cs_new:Nn\__erw_sys_datetime_hex: {\__erw_sys_datetime_join:nn{\__erw_sys_date_hex:}{\__erw_sys_time_hex:}}
+\cs_new:Nn\__erw_sys_jobnametimestamp_prefix:
 {
-    \__erw_int_range:nnn {}{0}{#1}
+  \erw_tl_join:nn
+  {\c_sys_jobname_str}
+  {\g__erw_sys_timestamp_delim_str}
 }
-\cs_set:Npn \erw_gset_map:N #1
+\cs_new:Nn\__erw_sys_jobnametimestamp:nn
 {
-    \erw_cs_gset_eq:NN \__erw_map:n #1
+  \erw_tl_join:nn
+  {\__erw_sys_jobnametimestamp_prefix:}
+  {\erw_sys_timestamp:nn{#1}{#2}}
 }
-\cs_set:Npn \erw_gset_map_inline:n #1
+\cs_new:Nn\__erw_sys_jobnametimestamp:
 {
-    \erw_cs_gset_inline:Nn \__erw_map:n {#1}
+  \erw_tl_join:nn
+  {\__erw_sys_jobnametimestamp_prefix:}
+  {\erw_sys_timestamp:}
 }
-\cs_set:Npn \erw_map:n #1
+\cs_new:Nn\__erw_sys_timestamp:nn
 {
-  \__erw_map:nn#1\q_recursion_tail\q_recursion_stop\q_recursion_tail\q_recursion_stop
+  \exp_args:No
+  \use:c{__erw_sys_\__erw_sys_datetime_period:n{#1}_\__erw_sys_datetime_base:n{#2}:}
 }
-\cs_set:Npn \__erw_map:nn #1 #2
+\cs_new_protected:Nn \__erw_sys_set_delim:nn
 {
-  \quark_if_recursion_tail_stop:n{#1}
-  \__erw_map:n{#1}  \__erw_map:nn{#2}
+  \use:c{tl_gset:N#1}
+  \g__erw_sys_timestamp_delim_str{#2}
 }
-\cs_new:Npn \__erw_map:n #1
+\keys_define:nn{__erw}
 {
-  \msg_error:nnn
-    {erw}
-    {generic}
-    {__erw_map:n~not~set}
+  sys / timestamp_delim .code:n =
+  {
+    \exp_last_unbraced:No
+    \__erw_sys_set_delim:nn{n}{#1}
+  },
+  sys / timestamp_delim  .value_required:n = true,
+  sys / timestamp_delim  .default:n = {-},
+  sys / timestamp_delim  .initial:n = {-}
 }
-\cs_set:Npn \erw_map:Nn
-  #1 % fun
-  #2 % tl
+\cs_new:Nn\erw_sys_jobnametimestamp:nn{\__erw_sys_jobnametimestamp:nn{#1}{#2}}
+\cs_new:Nn\erw_sys_jobnametimestamp:{\__erw_sys_jobnametimestamp:}
+\cs_new:Nn\erw_sys_timestamp_delimiter:
 {
-  \erw_cs_set_eq:NN \__erw_map:n #1
-  \erw_map:n{#2}
+  \use:N \g__erw_sys_timestamp_delim_str
 }
-\cs_set:Npn \erw_map_inline:nn
-  #1 % inl
-  #2 % tl
+\cs_new:Nn\erw_sys_timestamp:nn
 {
-  \erw_cs_set_inline:Nn \__erw_map:n {#1}
-  \erw_map:n{#2}
+  \__erw_sys_timestamp:nn{#1}{#2}
 }
-\cs_set:Npn \erw_apply:Nnn #1 #2 #3
+\cs_new:Nn\erw_sys_timestamp:
 {
-    #1{#2}{#3}
+  \__erw_sys_timestamp:nn{datetime}{16}
 }
-\cs_set:Npn \erw_apply:Nnnn #1 #2 #3 #4
+\tl_new:N \g__erw_tl_compose_tl
+\cs_new_protected:Nn \g__erw_tl_function:n
 {
-    #1{#2}{#3}{#4}
+  \msg_error:nnn
+  {erw}
+  {notset}
+  {\g__erw_tl_function:n}
 }
-\cs_set:Npn \erw_apply:Nnnnn #1 #2 #3 #4 #5
+\cs_set_protected:Nn \__erw_tl_map:nn
 {
-    #1{#2}{#3}{#4}{#5}
+  \quark_if_recursion_tail_stop:n{#1}
+  \g__erw_tl_function:n{#1}  \__erw_tl_map:nn{#2}
 }
-\cs_set:Npn \__erw_map_thread_at:Nnn #1 #2 #3
+\cs_set_protected:Nn \__erw_tl_map_thread_at:Nnn
 {
-     \erw_apply:Nn #1
-     {\exp_args:Nf\tl_item:nn {#3} {#2} }
+  #1
+  {\exp_args:Nf\tl_item:nn {#3} {#2} }
 }
-\cs_set:Npn \__erw_map_thread_at:Nnnn #1 #2 #3 #4
+\cs_set_protected:Nn \__erw_tl_map_thread_at:Nnnn
 {
-     \erw_apply:Nnn #1
-     {\exp_args:Nf\tl_item:nn {#3} {#2} }
-     {\exp_args:Nf\tl_item:nn {#4} {#2} }
+  #1
+  {\exp_args:Nf\tl_item:nn {#3} {#2} }
+  {\exp_args:Nf\tl_item:nn {#4} {#2} }
 }
-\cs_set:Npn \__erw_map_thread_at:Nnnnn #1 #2 #3 #4 #5
+\cs_set_protected:Nn \__erw_tl_map_thread_at:Nnnnn
 {
-     \erw_apply:Nnnn #1
-     {\exp_args:Nf\tl_item:nn {#3} {#2} }
-     {\exp_args:Nf\tl_item:nn {#4} {#2} }
-     {\exp_args:Nf\tl_item:nn {#5} {#2} }
+  #1
+  {\exp_args:Nf\tl_item:nn {#3} {#2} }
+  {\exp_args:Nf\tl_item:nn {#4} {#2} }
+  {\exp_args:Nf\tl_item:nn {#5} {#2} }
 }
-\cs_set:Npn \__erw_map_thread_at:Nnnnnn #1 #2 #3 #4 #5 #6
+\cs_set_protected:Nn \__erw_tl_map_thread_at:Nnnnnn
 {
-     \erw_apply:Nnnnn #1
-     {\exp_args:Nf\tl_item:nn {#3} {#2} }
-     {\exp_args:Nf\tl_item:nn {#4} {#2} }
-     {\exp_args:Nf\tl_item:nn {#5} {#2} }
-     {\exp_args:Nf\tl_item:nn {#6} {#2} }
+  #1
+  {\exp_args:Nf\tl_item:nn {#3} {#2} }
+  {\exp_args:Nf\tl_item:nn {#4} {#2} }
+  {\exp_args:Nf\tl_item:nn {#5} {#2} }
+  {\exp_args:Nf\tl_item:nn {#6} {#2} }
 }
-\cs_set:Npn \erw_map_thread_at:Nnn #1 #2 #3
+\cs_new:Nn \__erw_tl_separators:nn
 {
-    \exp_args:Nf\int_case:nnTF
-    {
-        \tl_count:n{#3}
-    }
-    {
-        {1}{ \__erw_map_thread_at:Nnn #1{#2}#3 }
-        {2}{ \__erw_map_thread_at:Nnnn #1{#2}#3 }
-        {3}{ \__erw_map_thread_at:Nnnnn #1{#2}#3 }
-        {4}{ \__erw_map_thread_at:Nnnnnn #1{#2}#3 }
-    }
-    {
-        % Do nothing
-    }
+  \int_case:nnTF {#1}
+  {
+    {1}
+    { \prg_replicate:nn{ 3 }{#2} }
+    {2}
     {
-        \msg_error:nnn{erw}
-            {generic}
-            {erw_map_thread_at:~count~of~#3~not~withing~1~to~4}
+      { \use_ii:nn #2 }
+      { \use_i:nn #2 }
+      { \use_i:nn #2 \use_ii:nn #2 }
     }
+    {3}{#2}
+  }
+  { \c_empty_tl }
+  {
+    \msg_error:nnnn { __erw }
+    { separ }
+    { \__erw_tl_separators:nn }
+    {#2}
+  }
 }
-\cs_set:Npn \erw_map_thread:Nn #1 #2
+\cs_generate_variant:Nn \__erw_tl_separators:nn { e }
+\cs_new:Nn \erw_tl_append_item:nn
 {
-    % TODO check that #2 is a matrix
-    \int_step_inline:nn
-    {
-        \exp_args:Nf \tl_count:n{ \tl_head:n{#2} }
-    }
-    {
-        \erw_map_thread_at:Nnn #1 {##1} {#2}
-    }
+  {#1{#2}}
+}
+\cs_new:Nn \erw_tl_fold:NN
+{
+  \use:c{tl_set:\g__erw_tl_fold_set_par_tl}
+  #2
+  {
+    \use:c{exp_args:\g__erw_tl_fold_apply_par_tl}{#1}{#2}
+  }
 }
-\int_new:N \__erw_numbrd_cs_int
-\cs_set:Npn \erw_numbrd_cs_name:n #1{__erw_numbrd_cs_\int_to_alph:n{#1}:n}
-\cs_set:Npn \erw_numbrd_cs_name_braced:n #1{{\erw_numbrd_cs_name:n{#1}}}
-\tl_set:Nn \__erw_numbrd_cs_name_tl {\erw_numbrd_cs_name:n{\__erw_numbrd_cs_int}}
-\cs_set:Npn \erw_numbrd_cs:nn #1 #2
+\cs_generate_variant:Nn \erw_tl_fold:NN {cN}
+\cs_new:Nn \erw_tl_gset_function:N
 {
-    \erw_apply:cn{__erw_numbrd_cs_\int_to_alph:n{#1}:n}{#2}
+  \erw_cs_gset_eq:NN \g__erw_tl_function:n #1
 }
-\cs_new_protected:Npn \erw_numbrd_cs_reset:
+\cs_new:Nn \erw_tl_gset_function:n
 {
-    \int_zero:N \__erw_numbrd_cs_int
-    \tl_set:Nn \__erw_numbrd_cs_ext_tl{}
+  \erw_cs_gset_inline:Nn \g__erw_tl_function:n {#1}
 }
-\cs_new_protected:Npn \erw_numbrd_cs_new:n #1
+\cs_new:Nn \erw_tl_last_item:n
 {
-    \int_incr:N \__erw_numbrd_cs_int
-    \erw_cs_set_inline:cn{\__erw_numbrd_cs_name_tl}
-    {
-        \token_if_cs:NTF
-            {#1}
-            {#1{##1}}
-            {#1}
-    }
+  \exp_args:Nof \tl_item:nn
+  {#1}
+  {
+    \tl_count:n{#1}
+  }
 }
-\cs_new:Npn \erw_numbrd_cs_names:nnn #1 #2 #3
+\cs_new:Nn \erw_tl_join:nn{#1#2}
+\cs_new:Nn \erw_tl_join:nnn{#1#2#3}
+\cs_new:Nn \erw_tl_join:nnnn{#1#2#3#4}
+\cs_new:Nn \erw_tl_join:nnnnn{#1#2#3#4#5}
+\cs_new_protected:Nn \erw_tl_map:n
 {
-    \int_step_function:nnnN { #1 }{ #2 }{ #3 } \erw_numbrd_cs_name:n
+  \__erw_tl_map:nn#1\q_recursion_tail\q_recursion_stop\q_recursion_tail\q_recursion_stop
 }
-\cs_new:Npn \erw_numbrd_cs_names_braced:nnn #1 #2 #3
+\cs_new_protected:Nn \erw_tl_map:Nn
 {
-    \int_step_function:nnnN { #1 }{ #2 }{ #3 } \erw_numbrd_cs_name_braced:n
-    % TODO \tl_range_braced:nnn?
+  \cs_set_eq:NN \g__erw_tl_function:n #1
+  \erw_tl_map:n{#2}
 }
-\cs_new:Npn \erw_numbrd_cs_names_braced:
+\cs_new_protected:Nn \erw_tl_map_inline:nn
 {
-    \erw_numbrd_cs_names_braced:nnn{1}{1}{\__erw_numbrd_cs_int}
+  \erw_cs_set_inline:Nn \g__erw_tl_function:n {#1}
+  \erw_tl_map:n{#2}
 }
-\NewDocumentCommand{\numbrdcsnew}{ s m }
+\cs_new:Nn \erw_tl_repeat:nn
 {
-    \IfBooleanTF{#1}
-        {}
-        { \erw_numbrd_cs_reset:{}}
-    \tl_map_function:nN {#2}\erw_numbrd_cs_new:n
+  \int_step_inline:nnnn{1}{1}{#1}{#2}
+}
+\cs_new:Nn \erw_tl_split:nnn
+{
+  \tl_head:n{#1}
+  \use:c{exp_args:#3} \tl_map_inline:nn
+  {
+    \tl_tail:n
+    {
+      #1
+    }
+  }{#2##1}
+}
+\cs_new:Nn \erw_tl_split:nn
+{
+  \erw_tl_split:nnn{#1}{#2}{Nf}
+}
+\cs_new_protected:Nn \erw_tl_map_thread_at:Nnn
+{
+  \exp_args:Nf\int_case:nnTF
+  {
+    \tl_count:n{#3}
+  }
+  {
+    {1}{ \__erw_tl_map_thread_at:Nnn #1{#2}#3 }
+    {2}{ \__erw_tl_map_thread_at:Nnnn #1{#2}#3 }
+    {3}{ \__erw_tl_map_thread_at:Nnnnn #1{#2}#3 }
+    {4}{ \__erw_tl_map_thread_at:Nnnnnn #1{#2}#3 }
+  }
+  {
+    % Do nothing
+  }
+  {
+    \msg_error:nnn{__erw}
+    {generic}
+    {erw_tl_map_thread_at:~count~of~#3~not~withing~1~to~4}
+  }
+}
+\cs_new_protected:Nn \erw_tl_map_thread:Nn
+{
+  \int_step_inline:nn
+  {
+    \exp_args:Nf \tl_count:n{ \tl_head:n{#2} }
+  }
+  {
+    \erw_tl_map_thread_at:Nnn #1 {##1} {#2}
+  }
 }
-\NewDocumentCommand{\numbrdcs}{ m m }
+\cs_new:Nn \erw_tl_separators:n
 {
-    \erw_numbrd_cs:nn{#1}{#2}
+  \__erw_tl_separators:en{ \tl_count:n{#1} }{#1}
 }
 \ExplSyntaxOff
 %% 
-%% Copyright (C) 2018 by Erwann Rogard
+%% Copyright (C) 2018-2020 by Erwann Rogard
 %% 
 %% This work may be distributed and/or modified under the
 %% conditions of the LaTeX Project Public License (LPPL), either
@@ -395,10 +509,8 @@
 %% This work is "maintained" (as per LPPL maintenance status) by
 %% Erwann Rogard.
 %% 
-%% This work consists of the file  erw-l3.dtx
-%% and the derived files   erw-l3.ins,
-%%                                 erw-l3.pdf and
-%%                                 erw-l3.sty.
+%% This work consists of the file erw-l3.dtx and the derived files:
+%% erw-l3.sty, and erw-l3.pdf.
 %% 
 %%
 %% End of file `erw-l3.sty'.