unravel (22sep15)

git-svn-id: svn://tug.org/texlive/trunk@38435 c570f23f-e606-0410-a88d-b1316a301751

1 files changed, 611 insertions, 419 deletions

diff --git a/Master/texmf-dist/tex/latex/unravel/unravel.sty b/Master/texmf-dist/tex/latex/unravel/unravel.sty
index 1665ce3acf4..630584380a7 100644
--- a/Master/texmf-dist/tex/latex/unravel/unravel.sty
+++ b/Master/texmf-dist/tex/latex/unravel/unravel.sty
@@ -11,7 +11,7 @@
 %% Communicate any suggestions for changing this package
 %% to Bruno Le Floch (blflatex@gmail.com).
 %% 
-%% File: unravel.dtx Copyright (C) 2013 Bruno Le Floch
+%% File: unravel.dtx Copyright (C) 2013, 2015 Bruno Le Floch
 %%
 %% It may be distributed and/or modified under the conditions of the
 %% LaTeX Project Public License (LPPL), either version 1.3c of this
@@ -21,80 +21,21 @@
 %%    http://www.latex-project.org/lppl.txt
 %%
 %% -----------------------------------------------------------------------
-\RequirePackage{expl3}[2013/07/01]
-\RequirePackage{l3str}[2013/04/24]
-\RequirePackage{gtl}[2013/07/28]
+\RequirePackage{expl3,xparse}[2015/09/11]
+\RequirePackage{gtl}[2015/09/21]
 \ProvidesExplPackage
-  {unravel} {2013/07/28} {0.0a} {Watching TeX digest tokens}
-\ior_new:N \g__unravel_prompt_ior
-\tl_new:N  \g__unravel_prompt_before_tl
-\int_new:N \l__unravel_prompt_tmpa_int
-\int_new:N \g__unravel_nonstop_int
-\int_new:N \g__unravel_noise_int
-\int_gset_eq:NN \g__unravel_noise_int \c_one
-\bool_new:N \l__unravel_debug_bool
-\int_new:N \g__unravel_step_int
-\str_new:N \g__unravel_action_text_str
-\int_new:N \g__unravel_max_action_int
-\int_new:N \g__unravel_max_output_int
-\int_new:N \g__unravel_max_prev_int
-\int_new:N \g__unravel_max_input_int
-\int_gset:Nn \g__unravel_max_action_int { 50 }
-\int_gset:Nn \g__unravel_max_output_int { 300 }
-\int_gset:Nn \g__unravel_max_prev_int { 300 }
-\int_gset:Nn \g__unravel_max_input_int { 300 }
-\bool_new:N \g__unravel_speedup_macros_bool
-\bool_gset_true:N \g__unravel_speedup_macros_bool
-\int_new:N \l__unravel_print_int
-\int_new:N \g__unravel_input_int
-\int_new:N \g__unravel_input_tmpa_int
-\tl_new:N \l__unravel_input_tmpa_tl
-\seq_new:N \g__unravel_prev_input_seq
-\tl_new:N \l__unravel_prev_input_tl
-\gtl_new:N \l__unravel_prev_input_gtl
-\gtl_new:N \g__unravel_output_gtl
-\gtl_new:N \l__unravel_head_gtl
-\tl_new:N  \l__unravel_head_tl
-\token_new:Nn \l__unravel_head_token { ? }
-\int_new:N \l__unravel_head_cmd_int
-\int_new:N \l__unravel_head_char_int
-\tl_new:N \l__unravel_head_meaning_tl
-\tl_new:N \l__unravel_tmpa_tl
-\gtl_new:N \l__unravel_tmpb_gtl
-\tl_new:N \g__unravel_tmpc_tl
-\seq_new:N \l__unravel_tmpa_seq
-\tl_new:N \l__unravel_defined_tl
-\tl_new:N \l__unravel_defining_tl
-\cs_new_eq:NN \__unravel_inaccessible:w ?
-\gtl_new:N \g__unravel_after_assignment_gtl
-\bool_new:N \g__unravel_set_box_allowed_bool
-\bool_new:N \g__unravel_name_in_progress_bool
-\group_begin:
-  \char_set_lccode:nn { `* } { `# }
-  \tex_lowercase:D
-    { \tl_const:Nn \c__unravel_parameters_tl { ^*1*2*3*4*5*6*7*8*9 } }
-\group_end:
-\int_new:N \g__unravel_val_level_int
-\tl_const:Nn \c__unravel_plus_tl { + }
-\tl_const:Nn \c__unravel_minus_tl { - }
-\tl_const:Nn \c__unravel_times_tl { * }
-\tl_const:Nn \c__unravel_over_tl { / }
-\tl_const:Nn \c__unravel_lq_tl { ` }
-\tl_const:Nn \c__unravel_rq_tl { ' }
-\tl_const:Nn \c__unravel_dq_tl { " }
-\tl_const:Nn \c__unravel_lp_tl { ( }
-\tl_const:Nn \c__unravel_rp_tl { ) }
-\tl_const:Nn \c__unravel_eq_tl { = }
-\tl_const:Nn \c__unravel_comma_tl { , }
-\tl_const:Nn \c__unravel_point_tl { . }
-\tl_new:N \g__unravel_if_limit_tl
-\int_new:N \g__unravel_if_limit_int
-\int_new:N \g__unravel_if_depth_int
-\int_new:N \l__unravel_if_nesting_int
-\seq_new:N \l__unravel_leaders_box_seq
-\int_new:N \g__unravel_ends_int
-\int_gset:Nn \g__unravel_ends_int { 3 }
-\gtl_const:Nx \c__unravel_frozen_relax_gtl { \if_int_compare:w 0 = 0 \fi: }
+  {unravel} {2015/09/22} {0.1} {Watching TeX digest tokens}
+\cs_if_exist:NF \str_range:nnn { \RequirePackage{l3str} }
+\cs_new_eq:NN \__unravel_currentgrouptype:      \etex_currentgrouptype:D
+\cs_new_protected_nopar:Npn \__unravel_set_escapechar:n
+  { \int_set:Nn \tex_escapechar:D }
+\cs_new_eq:NN \__unravel_everyeof:w             \etex_everyeof:D
+\cs_new_eq:NN \__unravel_everypar:w             \tex_everypar:D
+\cs_new_eq:NN \__unravel_hbox:w                 \tex_hbox:D
+\cs_new_eq:NN \__unravel_nullfont:              \tex_nullfont:D
+\cs_new_eq:NN \__unravel_the:w                  \tex_the:D
+\cs_new_eq:NN \c__unravel_prompt_ior \c_sixteen
+\cs_new_eq:NN \c__unravel_noprompt_ior \c_minus_one
 \cs_if_exist:NF \exp_last_unbraced:NNn
   { \cs_new_eq:NN \exp_last_unbraced:NNn \use:nnn }
 \cs_generate_variant:Nn \exp_last_unbraced:NNn { NNv }
@@ -121,21 +62,19 @@
 \cs_generate_variant:Nn \gtl_gset:Nn { c }
 \cs_generate_variant:Nn \gtl_gconcat:NNN { ccc , cNc }
 \cs_generate_variant:Nn \gtl_gclear:N { c }
+\cs_generate_variant:Nn \gtl_gclear_new:N { c }
+\cs_new_protected_nopar:Npn \__unravel_tmp:w { }
 \cs_new_protected:Npn \__unravel_tl_gset_input:Nnn #1#2#3
   {
     \group_begin:
-      \etex_everyeof:D \exp_after:wN { \token_to_str:N @ @ #1 }
+      \__unravel_everyeof:w \exp_after:wN { \token_to_str:N @ @ #1 }
       #2
       \tl_gclear:N #1
-      \str_if_eq_x:nnF
-        { \token_to_meaning:N \tex_input:D }
-        { \token_to_str:N \input }
-        { \msg_unravel:nnx { unravel } { internal } { input-prim } }
       \exp_after:wN \__unravel_tl_gset_input_aux:wN
       \exp_after:wN \prg_do_nothing:
         \tex_input:D \tl_to_str:n {#3} \scan_stop:
     \group_end:
-    \tl_gput_right:NV #1 \etex_everyeof:D
+    \tl_gput_right:NV #1 \__unravel_everyeof:w
   }
 \cs_generate_variant:Nn \__unravel_tl_gset_input:Nnn { Nno }
 \use:x
@@ -143,7 +82,6 @@
     \cs_new_protected:Npn \exp_not:N \__unravel_tl_gset_input_aux:wN
       ##1 \token_to_str:N @ @ ##2
   }   { \tl_gset:No #2 {#1} }
-\cs_new_eq:NN \__unravel_cs_case:NnF \tl_case:NnF
 \cs_new_nopar:Npn \__unravel_strip_escape:w
   {
     \tex_romannumeral:D
@@ -153,15 +91,6 @@
 \cs_new:Npn \__unravel_strip_escape_aux:N #1 { \c_zero }
 \cs_new:Npn \__unravel_strip_escape_aux:w #1#2
   { - \__int_value:w #1 \c_zero }
-\cs_new:Npn \__unravel_meaning_to_char:n #1
-  { \__unravel_meaning_to_char_auxi:w #1 \q_mark ~ {} ~ \q_mark \q_stop }
-\cs_new:Npn \__unravel_meaning_to_char_auxi:w #1 ~ #2 ~ #3 \q_mark #4 \q_stop
-  { \__unravel_meaning_to_char_auxii:w #3 ~ #3 ~ \q_stop }
-\cs_new:Npn \__unravel_meaning_to_char_auxii:w #1 ~ #2 ~ #3 \q_stop
-  { \tl_if_empty:nTF {#2} { ~ } {#2} }
-\cs_generate_variant:Nn \__unravel_meaning_to_char:n { o }
-\cs_new:Npn \__unravel_token_to_char:N #1
-  { \__unravel_meaning_to_char:o { \token_to_meaning:N #1 } }
 \cs_new:Npn \__unravel_to_str:n #1
   {
     \tl_if_head_eq_meaning:nNTF {#1} \scan_stop:
@@ -177,28 +106,64 @@
           #1 tl \q_mark \q_stop
       }
     \cs_new:Npn \__unravel_to_str_auxii:w ##1 #1 ##2 \q_mark ##3 \q_stop
-      { \cs_if_exist_use:cF { ##2 _to_str:n } { \tl_to_str:n } }
+      { \cs_if_exist_use:cF { __unravel_ ##2 _to_str:n } { \tl_to_str:n } }
   }
 \exp_args:No \__unravel_tmp:w { \tl_to_str:n { s__ } }
-\cs_new_protected:Npn \__unravel_prev_input_silent:n #1
+\cs_new:Npn \__unravel_gtl_to_str:n #1 { \__gtl_to_str:w #1 }
+\cs_new:Npn \__unravel_str_truncate_left:nn #1#2
   {
-    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_prev_input_tl
-    \tl_put_right:Nn \l__unravel_prev_input_tl {#1}
-    \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_prev_input_tl
+    \exp_args:Nf \__unravel_str_truncate_left_aux:nnn
+      { \str_count:n {#1} } {#1} {#2}
   }
-\cs_generate_variant:Nn \__unravel_prev_input_silent:n { V , x }
-\cs_new_protected:Npn \__unravel_prev_input:n #1
+\cs_new:Npn \__unravel_str_truncate_left_aux:nnn #1#2#3
   {
-    \__unravel_prev_input_silent:n {#1}
-    \__unravel_print_action:x { \tl_to_str:n {#1} }
+    \int_compare:nNnTF {#1} > {#3}
+      {
+        ( \int_eval:n { #1 - #3 + 25 } ~ more~chars ) ~
+        \str_range:nnn {#2} { #1 - #3 + 26 } {#1}
+      }
+      { \tl_to_str:n {#2} }
   }
-\cs_generate_variant:Nn \__unravel_prev_input:n { V , x }
-\cs_new_protected:Npn \__unravel_prev_input_gtl:N #1
+\cs_new:Npn \__unravel_str_truncate_right:nn #1#2
   {
-    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_prev_input_gtl
-    \gtl_concat:NNN \l__unravel_prev_input_gtl \l__unravel_prev_input_gtl #1
-    \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_prev_input_gtl
+    \exp_args:Nf \__unravel_str_truncate_right_aux:nnn
+      { \str_count:n {#1} } {#1} {#2}
+  }
+\cs_new:Npn \__unravel_str_truncate_right_aux:nnn #1#2#3
+  {
+    \int_compare:nNnTF {#1} > {#3}
+      {
+        \str_range:nnn {#2} { 1 } { #3 - 25 } ~
+        ( \int_eval:n { #1 - #3 + 25 } ~ more~chars )
+      }
+      { \tl_to_str:n {#2} }
+  }
+\cs_new_eq:NN \__unravel_exit_point: \prg_do_nothing:
+\cs_new:Npn \__unravel_exit:w #1 \__unravel_exit_point: { }
+\cs_new_eq:NN \__unravel_break_point: \prg_do_nothing:
+\cs_new:Npn \__unravel_break:w #1 \__unravel_break_point: { }
+\prg_new_conditional:Npnn \__unravel_cmd_if_internal: { TF }
+  {
+    \int_compare:nNnTF
+      \l__unravel_head_cmd_int < { \__unravel_tex_use:n { min_internal } }
+      { \prg_return_false: }
+      {
+        \int_compare:nNnTF
+          \l__unravel_head_cmd_int
+          > { \__unravel_tex_use:n { max_internal } }
+          { \prg_return_false: }
+          { \prg_return_true: }
+      }
   }
+\cs_new:Npn \__unravel_meaning_to_char:n #1
+  { \__unravel_meaning_to_char_auxi:w #1 \q_mark ~ {} ~ \q_mark \q_stop }
+\cs_new:Npn \__unravel_meaning_to_char_auxi:w #1 ~ #2 ~ #3 \q_mark #4 \q_stop
+  { \__unravel_meaning_to_char_auxii:w #3 ~ #3 ~ \q_stop }
+\cs_new:Npn \__unravel_meaning_to_char_auxii:w #1 ~ #2 ~ #3 \q_stop
+  { \tl_if_empty:nTF {#2} { ~ } {#2} }
+\cs_generate_variant:Nn \__unravel_meaning_to_char:n { o }
+\cs_new:Npn \__unravel_token_to_char:N #1
+  { \__unravel_meaning_to_char:o { \token_to_meaning:N #1 } }
 \prg_new_conditional:Npnn \__unravel_token_if_expandable:N #1
   { p , T ,  F , TF }
   {
@@ -223,18 +188,16 @@
       }
       { \prg_return_true: }
   }
-\cs_new_eq:NN \__unravel_exit_point: \prg_do_nothing:
-\cs_new:Npn \__unravel_exit:w #1 \__unravel_exit_point: { }
-\cs_new_eq:NN \__unravel_break_point: \prg_do_nothing:
-\cs_new:Npn \__unravel_break:w #1 \__unravel_break_point: { }
 \group_begin:
   \char_set_catcode_active:n { `Z }
   \prg_new_protected_conditional:Npnn \__unravel_token_if_definable:N #1
     { TF }
     {
       \group_begin:
-        \int_set:Nn \tex_escapechar:D { 92 }
-        \exp_args:No \tl_if_single:nTF { \token_to_str:N #1 }
+        \__unravel_set_escapechar:n { 92 }
+        \tl_set:Nx \l__unravel_tmpa_tl
+          { \exp_args:No \str_tail:n { \token_to_str:N #1 } }
+        \tl_if_empty:NTF \l__unravel_tmpa_tl
           {
             \exp_args:Nx \char_set_lccode:nn
               { ` \str_head:n {#1} } { `Z }
@@ -261,6 +224,123 @@
       }
       { \prg_return_false: }
   }
+\cs_new_protected:Npn \__unravel_prev_input_silent:n #1
+  {
+    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_prev_input_tl
+    \tl_put_right:Nn \l__unravel_prev_input_tl {#1}
+    \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_prev_input_tl
+  }
+\cs_generate_variant:Nn \__unravel_prev_input_silent:n { V , x }
+\cs_new_protected:Npn \__unravel_prev_input:n #1
+  {
+    \__unravel_prev_input_silent:n {#1}
+    \__unravel_print_action:x { \tl_to_str:n {#1} }
+  }
+\cs_generate_variant:Nn \__unravel_prev_input:n { V , x }
+\cs_new_protected:Npn \__unravel_prev_input_gtl:N #1
+  {
+    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_prev_input_gtl
+    \gtl_concat:NNN \l__unravel_prev_input_gtl \l__unravel_prev_input_gtl #1
+    \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_prev_input_gtl
+  }
+\cs_new_protected:Npn \__unravel_prev_input_join_get:nN #1
+  {
+    \int_case:nnF {#1}
+      {
+        { 2 } { \__unravel_join_get_aux:NNN \skip_eval:n \etex_glueexpr:D }
+        { 3 } { \__unravel_join_get_aux:NNN \muskip_eval:n \etex_muexpr:D }
+      }
+      {
+        \msg_error:nnn { unravel } { internal } { join-factor }
+        \__unravel_join_get_aux:NNN \use:n \prg_do_nothing:
+      }
+  }
+\cs_new_protected:Npn \__unravel_join_get_aux:NNN #1#2#3
+  {
+    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
+    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_tmpa_tl
+    \tl_set:Nx #3 { #1 { \l__unravel_tmpa_tl #2 \l__unravel_head_tl } }
+  }
+\tl_new:N \g__unravel_before_print_state_tl
+\tl_new:N  \g__unravel_before_prompt_tl
+\int_new:N \l__unravel_prompt_tmpa_int
+\int_new:N \g__unravel_nonstop_int
+\int_new:N \g__unravel_noise_int
+\int_gset_eq:NN \g__unravel_noise_int \c_one
+\bool_new:N \g__unravel_default_explicit_prompt_bool
+\bool_new:N \g__unravel_default_internal_debug_bool
+\bool_new:N \g__unravel_default_number_steps_bool
+\bool_gset_true:N \g__unravel_default_number_steps_bool
+\bool_new:N \g__unravel_default_welcome_message_bool
+\bool_gset_true:N \g__unravel_default_welcome_message_bool
+\bool_new:N \g__unravel_explicit_prompt_bool
+\bool_new:N \g__unravel_internal_debug_bool
+\bool_new:N \g__unravel_number_steps_bool
+\bool_new:N \g__unravel_welcome_message_bool
+\int_new:N \g__unravel_step_int
+\str_new:N \g__unravel_action_text_str
+\int_new:N \g__unravel_default_max_action_int
+\int_new:N \g__unravel_default_max_output_int
+\int_new:N \g__unravel_default_max_input_int
+\int_gset:Nn \g__unravel_default_max_action_int { 50 }
+\int_gset:Nn \g__unravel_default_max_output_int { 300 }
+\int_gset:Nn \g__unravel_default_max_input_int { 300 }
+\int_new:N \g__unravel_max_action_int
+\int_new:N \g__unravel_max_output_int
+\int_new:N \g__unravel_max_input_int
+\bool_new:N \g__unravel_speedup_macros_bool
+\bool_gset_true:N \g__unravel_speedup_macros_bool
+\int_new:N \l__unravel_print_int
+\int_new:N \g__unravel_input_int
+\int_new:N \g__unravel_input_tmpa_int
+\tl_new:N \l__unravel_input_tmpa_tl
+\seq_new:N \g__unravel_prev_input_seq
+\tl_new:N \l__unravel_prev_input_tl
+\gtl_new:N \l__unravel_prev_input_gtl
+\gtl_new:N \g__unravel_output_gtl
+\gtl_new:N \l__unravel_head_gtl
+\tl_new:N  \l__unravel_head_tl
+\token_new:Nn \l__unravel_head_token { ? }
+\int_new:N \l__unravel_head_cmd_int
+\int_new:N \l__unravel_head_char_int
+\tl_new:N \l__unravel_head_meaning_tl
+\tl_new:N \l__unravel_tmpa_tl
+\gtl_new:N \l__unravel_unused_gtl
+\gtl_new:N \l__unravel_tmpb_gtl
+\tl_new:N \g__unravel_tmpc_tl
+\seq_new:N \l__unravel_tmpa_seq
+\tl_new:N \l__unravel_defined_tl
+\tl_new:N \l__unravel_defining_tl
+\cs_new_eq:NN \__unravel_inaccessible:w ?
+\gtl_new:N \g__unravel_after_assignment_gtl
+\bool_new:N \g__unravel_set_box_allowed_bool
+\bool_new:N \g__unravel_name_in_progress_bool
+\group_begin:
+  \cs_set:Npx \__unravel_tmp:w #1 { \c_hash_str #1 }
+  \tl_const:Nx \c__unravel_parameters_tl
+    { ^ \tl_map_function:nN { 123456789 } \__unravel_tmp:w }
+\group_end:
+\int_new:N \g__unravel_val_level_int
+\tl_new:N \g__unravel_if_limit_tl
+\int_new:N \g__unravel_if_limit_int
+\int_new:N \g__unravel_if_depth_int
+\int_new:N \l__unravel_if_nesting_int
+\seq_new:N \l__unravel_leaders_box_seq
+\int_new:N \g__unravel_ends_int
+\int_gset:Nn \g__unravel_ends_int { 3 }
+\tl_const:Nn \c__unravel_plus_tl { + }
+\tl_const:Nn \c__unravel_minus_tl { - }
+\tl_const:Nn \c__unravel_times_tl { * }
+\tl_const:Nn \c__unravel_over_tl { / }
+\tl_const:Nn \c__unravel_lq_tl { ` }
+\tl_const:Nn \c__unravel_rq_tl { ' }
+\tl_const:Nn \c__unravel_dq_tl { " }
+\tl_const:Nn \c__unravel_lp_tl { ( }
+\tl_const:Nn \c__unravel_rp_tl { ) }
+\tl_const:Nn \c__unravel_eq_tl { = }
+\tl_const:Nn \c__unravel_comma_tl { , }
+\tl_const:Nn \c__unravel_point_tl { . }
+\gtl_const:Nx \c__unravel_frozen_relax_gtl { \if_int_compare:w 0 = 0 \fi: }
 \cs_new_protected:Npn \__unravel_tex_const:nn #1#2
   { \int_const:cn { c__unravel_tex_#1_int } {#2} }
 \cs_new:Npn \__unravel_tex_use:n #1 { \int_use:c { c__unravel_tex_#1_int } }
@@ -683,7 +763,7 @@
 \__unravel_tex_primitive:nnn { lefthyphenmin         } { assign_int } { 51 }
 \__unravel_tex_primitive:nnn { righthyphenmin        } { assign_int } { 52 }
 \__unravel_tex_primitive:nnn { holdinginserts        } { assign_int } { 53 }
-\__unravel_tex_primitive:nnn { errorcontegtlines     } { assign_int } { 54 }
+\__unravel_tex_primitive:nnn { errorcontextlines     } { assign_int } { 54 }
 \__unravel_tex_primitive:nnn { pdfoutput             } { assign_int } { 55 }
 \__unravel_tex_primitive:nnn { pdfcompresslevel      } { assign_int } { 56 }
 \__unravel_tex_primitive:nnn { pdfdecimaldigits      } { assign_int } { 57 }
@@ -1158,14 +1238,16 @@
 \cs_new_protected:Npn \__unravel_input_split_auxiii:w
     #1 \__unravel_input_split_end:
   {
+    \gtl_gclear_new:c
+      { g__unravel_input_ \int_use:N \g__unravel_input_tmpa_int _gtl }
     \gtl_gset:cn
       { g__unravel_input_ \int_use:N \g__unravel_input_tmpa_int _gtl } {#1}
     \int_gdecr:N \g__unravel_input_tmpa_int
   }
 \cs_new_protected_nopar:Npn \__unravel_input_gset:n
   {
-    \int_gset_eq:NN \g__unravel_input_int \c_one
-    \gtl_gset:cn { g__unravel_input_1_gtl }
+    \int_gzero:N \g__unravel_input_int
+    \__unravel_back_input:n
   }
 \cs_new_protected:Npn \__unravel_input_get:N #1
   {
@@ -1262,6 +1344,7 @@
 \cs_new_protected_nopar:Npn \__unravel_back_input:n
   {
     \int_gincr:N \g__unravel_input_int
+    \gtl_gclear_new:c { g__unravel_input_ \int_use:N \g__unravel_input_int _gtl }
     \gtl_gset:cn { g__unravel_input_ \int_use:N \g__unravel_input_int _gtl }
   }
 \cs_generate_variant:Nn \__unravel_back_input:n { x , V , o }
@@ -1308,21 +1391,20 @@
     \msg_error:nn { unravel } { missing-dollar }
     \__unravel_print_action:
   }
-\group_begin:
-  \char_set_lccode:nn { `. } { `: }
-  \tex_lowercase:D
-    {
-      \cs_new:Npn \__unravel_macro_split_do:NN #1
-        {
-          \exp_after:wN \__unravel_macro_split_do:wN
-          \token_to_meaning:N #1 \q_mark { } . -> \q_mark \use_none:nnnn
-          \q_stop
-        }
-      \cs_new:Npn \__unravel_macro_split_do:wN
-          #1 . #2 -> #3 \q_mark #4 #5 \q_stop #6
-          { #4 #6 {#1} {#2} {#3} }
-    }
-\group_end:
+\use:x
+  {
+    \exp_not:n { \cs_new:Npn \__unravel_macro_split_do:NN #1 }
+      {
+        \exp_not:n { \exp_after:wN \__unravel_macro_split_do:wN }
+        \exp_not:n { \token_to_meaning:N #1 \q_mark { } }
+        \tl_to_str:n { : } \exp_not:n { -> \q_mark \use_none:nnnn }
+        \exp_not:N \q_stop
+      }
+    \exp_not:n { \cs_new:Npn \__unravel_macro_split_do:wN }
+        \exp_not:n {#1} \tl_to_str:n { : } \exp_not:n { #2 -> }
+        \exp_not:n { #3 \q_mark #4 #5 \q_stop #6 }
+      { \exp_not:n { #4 #6 {#1} {#2} {#3} } }
+  }
 \cs_new:Npn \__unravel_macro_prefix:N #1
   { \__unravel_macro_split_do:NN #1 \use_i:nnn }
 \cs_new:Npn \__unravel_macro_parameter:N #1
@@ -1349,22 +1431,28 @@
   }
 \cs_new_protected_nopar:Npn \__unravel_macro_call_quick:
   {
-    \exp_after:wN \__unravel_macro_call_quick_loop:NN \l__unravel_tmpa_tl
+    \exp_after:wN \__unravel_macro_call_quick_loop:NNN \l__unravel_tmpa_tl
       { ? \use_none_delimit_by_q_stop:w } \q_stop
   }
-\cs_new_protected_nopar:Npn \__unravel_macro_call_quick_loop:NN #1#2
+\cs_new_protected:Npn \__unravel_macro_call_quick_loop:NNN #1#2#3
   {
     \use_none:n #2
     \__unravel_input_gpop_item:NF \l__unravel_tmpa_tl
-      { \msg_error:nn { unravel } { runaway-macro-parameter } }
+      { \__unravel_macro_call_quick_runaway:Nw #3 }
     \tl_put_right:Nx \l__unravel_head_tl
       { { \exp_not:V \l__unravel_tmpa_tl } }
-    \__unravel_macro_call_quick_loop:NN
+    \__unravel_macro_call_quick_loop:NNN
+    #3
+  }
+\cs_new_protected:Npn \__unravel_macro_call_quick_runaway:Nw #1#2 \q_stop
+  {
+    \msg_error:nnxx { unravel } { runaway-macro-parameter }
+      { \tl_to_str:N \l__unravel_head_tl } { \tl_to_str:n {#1} }
   }
 \cs_new_protected_nopar:Npn \__unravel_expand:
   {
     \__unravel_set_action_text:
-    \bool_if:NT \l__unravel_debug_bool
+    \bool_if:NT \g__unravel_internal_debug_bool
       {
         \__unravel_set_cmd:
         \iow_term:x { Exp:~\int_use:N \l__unravel_head_cmd_int }
@@ -1527,7 +1615,7 @@
       }
       {
         \msg_error:nn { unravel } { missing-font-id }
-        \__unravel_prev_input:n { \tex_nullfont:D }
+        \__unravel_prev_input:n { \__unravel_nullfont: }
         \__unravel_back_error:
       }
   }
@@ -1573,7 +1661,7 @@
     \__unravel_prev_input_silent:V \l__unravel_tmpa_tl
     \__unravel_set_action_text:
     \__unravel_set_action_text:x
-      { \g__unravel_action_text_str = ~ \tl_to_str:N \l__unravel_tmpa_tl }
+      { \g__unravel_action_text_str \use:n { ~ => ~ } \tl_to_str:N \l__unravel_tmpa_tl }
     \int_compare:nNnF {#3} > { 3 } { \__unravel_print_action: }
     \int_gset:Nn \g__unravel_val_level_int {#1}
   }
@@ -1592,7 +1680,7 @@
         { 76 } { 3                         } % assign_mu_glue
         { 77 } { 1 \__unravel_scan_font_dimen:    } % assign_font_dimen
         { 78 } { 0 \__unravel_scan_font_int:      } % assign_font_int
-        { 79 } { 0                         } % set_aux
+        { 79 } { \__unravel_thing_set_aux:        } % set_aux
         { 80 } { 0                         } % set_prev_graf
         { 81 } { 1                         } % set_page_dimen
         { 82 } { 0                         } % set_page_int
@@ -1606,6 +1694,8 @@
       }
       { 8 }
   }
+\cs_new_nopar:Npn \__unravel_thing_set_aux:
+  { \int_compare:nNnTF \l__unravel_head_char_int = { 1 } { 1 } { 0 } }
 \cs_new_nopar:Npn \__unravel_thing_last_item:
   {
     \int_compare:nNnTF \l__unravel_head_char_int < { 26 }
@@ -1669,7 +1759,7 @@
         { 2 } \skip_eval:n
         { 3 } \muskip_eval:n
       }
-      { \tex_the:D }
+      { \__unravel_the:w }
   }
 \cs_new_protected:Npn \__unravel_scan_expr:N #1
   { \__unravel_scan_expr_aux:NN #1 \c_false_bool }
@@ -1760,16 +1850,9 @@
   {
     \__unravel_scan_signs:
     \__unravel_set_cmd:
-    \int_compare:nNnTF
-      \l__unravel_head_cmd_int < { \__unravel_tex_use:n { min_internal } }
+    \__unravel_cmd_if_internal:TF
+      { \__unravel_scan_something_internal:n { 0 } }
       { \__unravel_scan_int_char: }
-      {
-        \int_compare:nNnTF
-          \l__unravel_head_cmd_int
-          > { \__unravel_tex_use:n { max_internal } }
-          { \__unravel_scan_int_char: }
-          { \__unravel_scan_something_internal:n { 0 } }
-      }
   }
 \cs_new_protected_nopar:Npn \__unravel_scan_int_char:
   {
@@ -1825,50 +1908,43 @@
     }
   }
 \cs_new_protected_nopar:Npn \__unravel_scan_normal_dimen:
-  { \__unravel_scan_dimen:NN \c_false_bool \c_false_bool }
-\cs_new_protected:Npn \__unravel_scan_dimen:NN #1#2
+  { \__unravel_scan_dimen:nN { 2 } \c_false_bool }
+\cs_new_protected:Npn \__unravel_scan_dimen:nN #1#2
   {
     \__unravel_scan_signs:
     \seq_gput_right:Nn \g__unravel_prev_input_seq { }
     \__unravel_set_cmd:
-    \int_compare:nNnTF
-      \l__unravel_head_cmd_int < { \__unravel_tex_use:n { min_internal } }
-      { \__unravel_scan_dimen_char:NN #1#2 }
+    \__unravel_cmd_if_internal:TF
       {
-        \int_compare:nNnTF
-          \l__unravel_head_cmd_int
-          > { \__unravel_tex_use:n { max_internal } }
-          { \__unravel_scan_dimen_char:NN #1#2 }
+        \int_compare:nNnTF {#1} = { 3 }
           {
-            \bool_if:NTF #1
+            \__unravel_scan_something_internal:n { 3 }
+            \int_case:nnF \g__unravel_val_level_int
               {
-                \__unravel_scan_something_internal:n { 3 }
-                \int_case:nnF \g__unravel_val_level_int
-                  {
-                    { 0 } { \__unravel_scan_dim_unit:NN #1 #2 }
-                    { 3 } { }
-                  }
-                  {
-                    \msg_error:nn { unravel } { incompatible-units }
-                    % ^^A todo: error recovery
-                  }
+                { 0 } { \__unravel_scan_dim_unit:nN {#1} #2 }
+                { 3 } { }
               }
               {
-                \__unravel_scan_something_internal:n { 2 }
-                \int_case:nnF \g__unravel_val_level_int
-                  {
-                    { 0 } { \__unravel_scan_dim_unit:NN #1#2 }
-                    { 3 } % ^^A todo: error recovery
-                    { \msg_error:nn { unravel } { incompatible-units } }
-                  }
-                  { }
+                \msg_error:nn { unravel } { incompatible-units }
+                % ^^A todo: error recovery
               }
           }
+          {
+            \__unravel_scan_something_internal:n { 1 }
+            \int_case:nnF \g__unravel_val_level_int
+              {
+                { 0 } { \__unravel_scan_dim_unit:nN {#1} #2 }
+                { 3 } % ^^A todo: error recovery
+                { \msg_error:nn { unravel } { incompatible-units } }
+              }
+              { }
+          }
       }
+      { \__unravel_scan_dimen_char:nN {#1} #2 }
     \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
     \__unravel_prev_input_silent:V \l__unravel_head_tl
   }
-\cs_new_protected:Npn \__unravel_scan_dimen_char:NN #1#2
+\cs_new_protected:Npn \__unravel_scan_dimen_char:nN #1#2
   {
     \tl_if_eq:NNT \l__unravel_head_tl \c__unravel_comma_tl
       { \tl_set_eq:NN \l__unravel_head_tl \c__unravel_point_tl }
@@ -1896,9 +1972,9 @@
             \__unravel_scan_int:
           }
       }
-    \__unravel_scan_dim_unit:NN #1#2
+    \__unravel_scan_dim_unit:nN {#1} #2
   }
-\cs_new_protected:Npn \__unravel_scan_dim_unit:NN #1#2
+\cs_new_protected:Npn \__unravel_scan_dim_unit:nN #1#2
   {
     \bool_if:NT #2
       {
@@ -1910,35 +1986,16 @@
       }
     \__unravel_get_x_non_blank:
     \__unravel_set_cmd:
-    \int_compare:nNnTF
-      \l__unravel_head_cmd_int < { \__unravel_tex_use:n { min_internal } }
-      { \__unravel_back_input: }
+    \__unravel_cmd_if_internal:TF
       {
-        \int_compare:nNnTF
-          \l__unravel_head_cmd_int
-          > { \__unravel_tex_use:n { max_internal } }
-          { \__unravel_back_input: }
-          {
-            \seq_gput_right:Nn \g__unravel_prev_input_seq { }
-            \bool_if:NTF #1
-              { \__unravel_scan_something_internal:n { 3 } }
-              { \__unravel_scan_something_internal:n { 2 } }
-            \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
-            \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_tmpa_tl
-            \tl_set:Nx \l__unravel_tmpa_tl
-              {
-                \bool_if:NTF #1 \muskip_eval:n \skip_eval:n
-                  {
-                    \l__unravel_tmpa_tl
-                    \bool_if:NTF #1 \etex_muexpr:D \etex_glueexpr:D
-                    \l__unravel_head_tl
-                  }
-              }
-            \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_tmpa_tl
-            \__unravel_break:w
-          }
+        \seq_gput_right:Nn \g__unravel_prev_input_seq { }
+        \__unravel_scan_something_internal:n {#1}
+        \__unravel_prev_input_join_get:nN {#1} \l__unravel_tmpa_tl
+        \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_tmpa_tl
+        \__unravel_break:w
       }
-    \bool_if:NT #1
+      { \__unravel_back_input: }
+    \int_compare:nNnT {#1} = { 3 }
       {
         \__unravel_scan_keyword:nT { mM uU } { \__unravel_break:w }
         \msg_error:nn { unravel } { missing-mudim }
@@ -1985,47 +2042,34 @@
   { \__unravel_scan_glue:n { 3 } }
 \cs_new_protected:Npn \__unravel_scan_glue:n #1
   {
-    \int_compare:nNnTF {#1} = { 2 }
-      { \__unravel_scan_glue_aux:nN {#1} \c_false_bool }
-      { \__unravel_scan_glue_aux:nN {#1} \c_true_bool }
-  }
-\cs_new_protected:Npn \__unravel_scan_glue_aux:nN #1#2
-  {
+    \seq_gput_right:Nn \g__unravel_prev_input_seq { }
     \__unravel_scan_signs:
     \seq_gput_right:Nn \g__unravel_prev_input_seq { }
     \__unravel_set_cmd:
-    \int_compare:nNnTF
-      \l__unravel_head_cmd_int < { \__unravel_tex_use:n { min_internal } }
-      { \__unravel_back_input: \__unravel_scan_dimen:NN #2 \c_false_bool }
+    \__unravel_cmd_if_internal:TF
       {
-        \int_compare:nNnTF
-          \l__unravel_head_cmd_int
-          > { \__unravel_tex_use:n { max_internal } }
+        \__unravel_scan_something_internal:n {#1}
+        \int_case:nnF \g__unravel_val_level_int
           {
-            \__unravel_back_input:
-            \__unravel_scan_dimen:NN #2 \c_false_bool
+            { 0 } { \__unravel_scan_dimen:nN {#1} \c_false_bool }
+            {#1} { \__unravel_break:w }
           }
           {
-            \__unravel_scan_something_internal:n {#1}
-            \int_case:nnF \g__unravel_val_level_int
-              {
-                { 0 } { \__unravel_scan_dimen:NN #2 \c_false_bool }
-                { 1 } { \bool_if:NT #2 { \msg_error: } } % ^^A todo: ??
-              }
-              {
-                \int_compare:nNnF \g__unravel_val_level_int = {#1}
-                  { \msg_error:nn { unravel } { incompatible-units } }
-                \__unravel_break:w
-              }
+            \int_compare:nNnF { \g__unravel_val_level_int + #1 } = 3
+              { \msg_error:nn { unravel } { incompatible-units } }
           }
       }
+      { \__unravel_back_input: \__unravel_scan_dimen:nN {#1} \c_false_bool }
+    \__unravel_prev_input_join_get:nN {#1} \l__unravel_tmpa_tl
+    \seq_gput_right:Nn \g__unravel_prev_input_seq { }
+    \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_tmpa_tl
     \__unravel_scan_keyword:nT { pP lL uU sS }
-      { \__unravel_scan_dimen:NN #2 \c_true_bool }
+      { \__unravel_scan_dimen:nN {#1} \c_true_bool }
     \__unravel_scan_keyword:nT { mM iI nN uU sS }
-      { \__unravel_scan_dimen:NN #2 \c_true_bool }
+      { \__unravel_scan_dimen:nN {#1} \c_true_bool }
     \__unravel_break_point:
-    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
-    \__unravel_prev_input_silent:V \l__unravel_head_tl
+    \__unravel_prev_input_join_get:nN {#1} \l__unravel_tmpa_tl
+    \__unravel_prev_input_silent:V \l__unravel_tmpa_tl
   }
 \cs_new_protected_nopar:Npn \__unravel_scan_file_name:
   {
@@ -2235,11 +2279,12 @@
       {
         \bool_if:NTF #1
           {
-            \__unravel_cs_case:NnF \l__unravel_head_token
+            \int_case:nnTF \l__unravel_head_cmd_int
               {
-                \tex_hrule:D { \__unravel_do_leaders_rule: }
-                \tex_vrule:D { \__unravel_do_leaders_rule: }
+                { \__unravel_tex_use:n { hrule } } { }
+                { \__unravel_tex_use:n { vrule } } { }
               }
+              { \__unravel_do_leaders_rule: }
               { \__unravel_do_box_error: }
           }
           { \__unravel_do_box_error: }
@@ -2304,7 +2349,7 @@
   }
 \cs_new_protected:Npn \__unravel_do_box_explicit:N #1
   {
-    \token_if_eq_meaning:NNTF \l__unravel_head_token \tex_hbox:D
+    \token_if_eq_meaning:NNTF \l__unravel_head_token \__unravel_hbox:w
       { \__unravel_box_hook:N \tex_everyhbox:D }
       { \__unravel_box_hook:N \tex_everyvbox:D }
       % ^^A todo: TeX calls |normal_paragraph| here.
@@ -2339,7 +2384,7 @@
         \__unravel_print_action:
         \__unravel_back_input:o {##1}
         \__unravel_set_action_text:x
-          { \token_to_meaning:N #1 \tl_to_str:o {##1} }
+          { \token_to_meaning:N #1 = \tl_to_str:o {##1} }
         \tl_if_empty:oF {##1} { \__unravel_print_action: }
       }
   }
@@ -2363,42 +2408,29 @@
       { \prg_return_true: }
       { \prg_return_false: }
   }
-\group_begin:
-  \char_set_catcode_other:n { 0 }
-  \cs_new_protected:Npn \__unravel_char:n #1
-    {
-      \tex_char:D #1 \scan_stop:
-      \__unravel_charcode_if_safe:nTF {#1}
-        {
-          \group_begin:
-          \char_set_lccode:nn { 0 } {#1}
-          \tex_lowercase:D
-            { \group_end: \tl_set:Nn \l__unravel_tmpa_tl { ^^@ } }
-        }
-        {
-          \tl_set:Nx \l__unravel_tmpa_tl
-            { \exp_not:N \char \int_eval:n {#1} ~ }
-        }
-      \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_tmpa_tl
-      \__unravel_print_action:x { \tl_to_str:N \l__unravel_tmpa_tl }
-    }
-\group_end:
+\cs_new_protected:Npn \__unravel_char:n #1
+  {
+    \tex_char:D #1 \scan_stop:
+    \__unravel_charcode_if_safe:nTF {#1}
+      { \tl_set:Nx \l__unravel_tmpa_tl { \char_generate:nn {#1} { 12 } } }
+      {
+        \tl_set:Nx \l__unravel_tmpa_tl
+          { \exp_not:N \char \int_eval:n {#1} ~ }
+      }
+    \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_tmpa_tl
+    \__unravel_print_action:x { \tl_to_str:N \l__unravel_tmpa_tl }
+  }
 \cs_generate_variant:Nn \__unravel_char:n { V , x }
-\group_begin:
-  \char_set_catcode_other:n { 0 }
-  \cs_new_protected:Npn \__unravel_char_in_mmode:n #1
-    {
-      \int_compare:nNnTF { \tex_mathcode:D #1 } = { "8000 }
-        { % math active
-          \group_begin:
-          \char_set_lccode:nn { 0 } { \l__unravel_tmpa_tl }
-          \tex_lowercase:D
-            { \group_end: \gtl_set:Nn \l__unravel_head_gtl { ^^@ } }
-          \__unravel_back_input:
-        }
-        { \__unravel_char:n {#1} }
-    }
-\group_end:
+\cs_new_protected:Npn \__unravel_char_in_mmode:n #1
+  {
+    \int_compare:nNnTF { \tex_mathcode:D #1 } = { "8000 }
+      { % math active
+        \gtl_set:Nx \l__unravel_head_gtl
+          { \char_generate:nn {#1} { 12 } }
+        \__unravel_back_input:
+      }
+      { \__unravel_char:n {#1} }
+  }
 \cs_generate_variant:Nn \__unravel_char_in_mmode:n { V , x }
 \cs_new_protected:Npn \__unravel_mathchar:n #1
   {
@@ -2411,10 +2443,10 @@
 \cs_generate_variant:Nn \__unravel_mathchar:n { x }
 \cs_new_protected:Npn \__unravel_new_graf:N #1
   {
-    \tl_set:NV \l__unravel_tmpa_tl \tex_everypar:D
-    \tex_everypar:D { }
+    \tl_set:NV \l__unravel_tmpa_tl \__unravel_everypar:w
+    \__unravel_everypar:w { }
     \bool_if:NTF #1 { \tex_indent:D } { \tex_noindent:D }
-    \exp_args:NV \tex_everypar:D \l__unravel_tmpa_tl
+    \exp_args:NV \__unravel_everypar:w \l__unravel_tmpa_tl
     \__unravel_back_input:V \l__unravel_tmpa_tl
     \__unravel_print_action:x
       {
@@ -2435,7 +2467,7 @@
   }
 \cs_new_protected_nopar:Npn \__unravel_handle_left_brace:
   {
-    \int_case:nnF \etex_currentgrouptype:D
+    \int_case:nnF \__unravel_currentgrouptype:
       {
         { 1 } { \__unravel_end_simple_group: } % simple
         { 2 } { \__unravel_end_box_group: } % hbox
@@ -2445,7 +2477,7 @@
         { 6 } { \__unravel_end_align_group: } % align
         { 7 } { \__unravel_end_no_align_group: } % no_align
         { 8 } { \__unravel_end_output_group: } % output
-        { 9 } { \__unravel_end_math_group: } % math
+        { 9 } { \__unravel_end_simple_group: } % math
         { 10 } { \__unravel_end_disc_group: } % disc
         { 11 } { \__unravel_end_graf: \__unravel_end_simple_group: } % insert
         { 12 } { \__unravel_end_graf: \__unravel_end_simple_group: } % vcenter
@@ -2487,14 +2519,14 @@
   }
 \cs_new_protected_nopar:Npn \__unravel_off_save:
   {
-    \int_compare:nNnTF \etex_currentgrouptype:D = { 0 }
+    \int_compare:nNnTF \__unravel_currentgrouptype: = { 0 }
       { % bottom-level
         \msg_error:nnx { unravel } { extra-close }
           { \token_to_meaning:N \l__unravel_head_token }
       }
       {
         \__unravel_back_input:
-        \int_case:nnF \etex_currentgrouptype:D
+        \int_case:nnF \__unravel_currentgrouptype:
           {
             { 14 } % semi_simple_group
               { \gtl_set:Nn \l__unravel_head_gtl { \group_end: } }
@@ -2542,10 +2574,44 @@
         \__unravel_back_input:
       }
   }
+\cs_new_protected_nopar:Npn \__unravel_goto_inner_math:
+  {
+    \__unravel_box_hook:N \tex_everymath:D
+    $ % $
+    \__unravel_box_hook_end:
+  }
+\cs_new_protected_nopar:Npn \__unravel_goto_display_math:
+  {
+    \__unravel_box_hook:N \tex_everydisplay:D
+    $ $
+    \__unravel_box_hook_end:
+  }
+\cs_new_protected_nopar:Npn \__unravel_after_math:
+  {
+    \mode_if_inner:TF
+      {
+        \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_head_tl
+        $ % $
+      }
+      {
+        \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_head_tl
+        \__unravel_get_x_next:
+        \token_if_eq_catcode:NNF
+          \l__unravel_head_token \c_math_toggle_token
+          {
+            \__unravel_back_input:
+            \tl_set:Nn \l__unravel_head_tl { $ } % $
+            \msg_error:nn { unravel } { missing-dollar }
+          }
+        \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_head_tl
+        $ $
+      }
+    \__unravel_print_action:
+  }
 \cs_new_protected_nopar:Npn \__unravel_do_step:
   {
     \__unravel_set_action_text:
-    \bool_if:NT \l__unravel_debug_bool
+    \bool_if:NT \g__unravel_internal_debug_bool
       { \iow_term:x { Cmd:~\int_use:N \l__unravel_head_cmd_int } }
     \cs_if_exist_use:cF
       { __unravel_cmd_ \int_use:N \l__unravel_head_cmd_int : }
@@ -2569,18 +2635,23 @@
         \mode_if_math:TF
           {
             \int_compare:nNnTF
-              \etex_currentgrouplevel:D = { 15 } % math_shift_group
+              \__unravel_currentgrouptype: = { 15 } % math_shift_group
               { \__unravel_after_math: }
               { \__unravel_off_save: }
           }
           {
+            \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_head_tl
             \__unravel_get_next:
             \token_if_eq_catcode:NNTF
               \l__unravel_head_token \c_math_toggle_token
               {
                 \mode_if_inner:TF
                   { \__unravel_back_input: \__unravel_goto_inner_math: }
-                  { \__unravel_goto_display_math: }
+                  {
+                    \gtl_gput_right:NV
+                      \g__unravel_output_gtl \l__unravel_head_tl
+                    \__unravel_goto_display_math:
+                  }
               }
               { \__unravel_back_input: \__unravel_goto_inner_math: }
           }
@@ -2600,10 +2671,45 @@
   {
     \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_head_tl
     \__unravel_print_action:
-    \__unravel_scan_math:
-    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
-    \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_head_tl
-    \tl_use:N \l__unravel_head_tl \scan_stop:
+    \__unravel_get_x_non_relax:
+    \__unravel_set_cmd:
+    \int_case:nnTF \l__unravel_head_cmd_int
+      {
+        { \__unravel_tex_use:n { the_char } }
+          { \__unravel_prev_input:V \l__unravel_head_tl }
+        { \__unravel_tex_use:n { other_char } }
+          { \__unravel_prev_input:V \l__unravel_head_tl }
+        { \__unravel_tex_use:n { char_given } }
+          { \__unravel_prev_input:V \l__unravel_head_tl }
+        { \__unravel_tex_use:n { char_num } }
+          {
+            \__unravel_prev_input:V \l__unravel_head_tl
+            \__unravel_scan_int:
+          }
+        { \__unravel_tex_use:n { math_char_num } }
+          {
+            \__unravel_prev_input:V \l__unravel_head_tl
+            \__unravel_scan_int:
+          }
+        { \__unravel_tex_use:n { math_given } }
+          { \__unravel_prev_input:V \l__unravel_head_tl }
+        { \__unravel_tex_use:n { delim_num } }
+          { \__unravel_prev_input:V \l__unravel_head_tl \__unravel_scan_int: }
+      }
+      {
+        \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
+        \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_head_tl
+        \tl_use:N \l__unravel_head_tl \scan_stop:
+      }
+      {
+        \__unravel_back_input:
+        \__unravel_scan_left_brace:
+        \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
+        \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_head_tl
+        \gtl_gconcat:NNN \g__unravel_output_gtl
+          \g__unravel_output_gtl \c_group_begin_gtl
+        \tl_use:N \l__unravel_head_tl \c_group_begin_token
+      }
     \__unravel_print_action:x { \tl_to_str:N \l__unravel_head_tl }
   }
 \__unravel_new_tex_cmd:nn { endv }                                 % 9
@@ -2657,7 +2763,7 @@
                 \__unravel_back_input:
                 \__unravel_back_input:n
                   {
-                    \tex_hbox:D to \tex_hsize:D { }
+                    \__unravel_hbox:w to \tex_hsize:D { }
                     \tex_vfill:D
                     \tex_penalty:D - '10000000000 ~
                   }
@@ -2823,8 +2929,8 @@
     \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_head_tl
     \__unravel_print_action:
     \token_if_eq_meaning:NNTF \l__unravel_head_token \tex_kern:D
-      { \__unravel_scan_dimen:NN \c_true_bool \c_false_bool }
-      { \__unravel_scan_dimen:NN \c_false_bool \c_false_bool }
+      { \__unravel_scan_dimen:nN { 2 } \c_false_bool }
+      { \__unravel_scan_dimen:nN { 3 } \c_false_bool }
     \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
     \tl_use:N \l__unravel_head_tl \scan_stop:
     \__unravel_print_action:x { \tl_to_str:N \l__unravel_head_tl }
@@ -2908,7 +3014,7 @@
       {
         \int_compare:nNnT \l__unravel_head_char_int = { 1 } % indent
           {
-            \tex_hbox:D width \tex_parindent:D { }
+            \__unravel_hbox:w width \tex_parindent:D { }
             \gtl_gput_right:NV \g__unravel_output_gtl \l__unravel_head_tl
           }
         \__unravel_print_action:
@@ -3563,7 +3669,7 @@
       { \__unravel_scan_font_int: } { \__unravel_scan_int: }
   }
 \__unravel_prefixed_new:nn { set_aux }                             % 79
-  { % prevdepth = 1, spacefactor = 0
+  { % prevdepth = 1, spacefactor = 102
     \int_compare:nNnTF \l__unravel_head_char_int = \c_one
       { \__unravel_assign_value:nn { } { \__unravel_scan_normal_dimen: } }
       { \__unravel_assign_value:nn { } { \__unravel_scan_int: } }
@@ -3737,25 +3843,34 @@
 \__unravel_prefixed_new:nn { set_interaction }                     % 100
   {
     \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_tmpa_tl
-    \tl_put_right:NV \l__unravel_head_tl \l__unravel_tmpa_tl
+    \tl_put_left:NV \l__unravel_head_tl \l__unravel_tmpa_tl
     \tl_use:N \l__unravel_head_tl \scan_stop:
     \__unravel_print_action:x { \tl_to_str:N \l__unravel_head_tl }
   }
 \__unravel_prefixed_new:nn { letterspace_font }                    % 101
   {
-    % ^^A todo...
-    % new_letterspaced_font(a);
-    \msg_error:nnx { unravel } { not-implemented } { letterspace-font }
-    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
-    \__unravel_omit_after_assignment:w
+    \__unravel_prev_input_silent:V \l__unravel_head_tl
+    \__unravel_set_action_text:x { \tl_to_str:N \l__unravel_head_tl }
+    \__unravel_scan_r_token:
+    \__unravel_print_action:x
+      { \g__unravel_action_text_str \tl_to_str:N \l__unravel_defined_tl }
+    \exp_after:wN \cs_set_eq:NN \l__unravel_defined_tl \__unravel_nullfont:
+    \__unravel_scan_optional_equals:
+    \__unravel_scan_font_ident:
+    \__unravel_scan_int:
+    \__unravel_assign_token:n { }
   }
 \__unravel_prefixed_new:nn { pdf_copy_font }                       % 102
   {
-    % ^^A todo...
-    % make_font_copy(a);
-    \msg_error:nnx { unravel } { not-implemented } { pdf-copy-font }
-    \seq_gpop_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
-    \__unravel_omit_after_assignment:w
+    \__unravel_prev_input_silent:V \l__unravel_head_tl
+    \__unravel_set_action_text:x { \tl_to_str:N \l__unravel_head_tl }
+    \__unravel_scan_r_token:
+    \__unravel_print_action:x
+      { \g__unravel_action_text_str \tl_to_str:N \l__unravel_defined_tl }
+    \exp_after:wN \cs_set_eq:NN \l__unravel_defined_tl \__unravel_nullfont:
+    \__unravel_scan_optional_equals:
+    \__unravel_scan_font_ident:
+    \__unravel_assign_token:n { }
   }
 \__unravel_prefixed_new:nn { register }                            % 89
   { \__unravel_do_register:N \c_zero }
@@ -3938,7 +4053,7 @@
   {
     \int_case:nnF \l__unravel_head_char_int
       {
-        { 1 } { \__unravel_print_action: } % \endinput
+        { 1 } { \__unravel_endinput: } % \endinput
         { 2 } { \__unravel_scantokens: } % \scantokens
       }
       { % 0=\input
@@ -3946,6 +4061,11 @@
           { \__unravel_insert_relax: } { \__unravel_input: }
       }
   }
+\cs_new_protected_nopar:Npn \__unravel_endinput:
+  {
+    \msg_warning:nn { unravel } { endinput-ignored }
+    \__unravel_print_action:
+  }
 \cs_new_protected_nopar:Npn \__unravel_scantokens:
   {
     \seq_gput_right:Nn \g__unravel_prev_input_seq { }
@@ -4142,7 +4262,7 @@
         \fi:
         \int_incr:N \l__unravel_if_nesting_int
         \fi:
-        \__unravel_input_gpop:N \l__unravel_tmpa_gtl
+        \__unravel_input_gpop:N \l__unravel_unused_gtl
         \int_compare:nNnTF \l__unravel_if_nesting_int = \c_zero
           { \__unravel_pass_text: }
           { \__unravel_pass_text_nested: }
@@ -4334,7 +4454,7 @@
   {
     \seq_gput_right:NV \g__unravel_prev_input_seq \l__unravel_head_tl
     \__unravel_print_action:
-    \bool_if:NT \l__unravel_debug_bool { \iow_term:n { {\ifcase level~#1} } }
+    \bool_if:NT \g__unravel_internal_debug_bool { \iow_term:n { {\ifcase level~#1} } }
     \__unravel_scan_int:
     \seq_get_right:NN \g__unravel_prev_input_seq \l__unravel_head_tl
     \tl_set:Nx \l__unravel_head_tl { \tl_tail:N \l__unravel_head_tl }
@@ -4433,7 +4553,7 @@
 \cs_new_protected:Npn \__unravel_set_action_text:x #1
   {
     \group_begin:
-      \int_set:Nn \tex_escapechar:D { 92 }
+      \__unravel_set_escapechar:n { 92 }
       \str_gset:Nx \g__unravel_action_text_str {#1}
     \group_end:
   }
@@ -4449,7 +4569,8 @@
 \cs_new_protected:Npn \__unravel_print_state:
   {
     \group_begin:
-      \int_set:Nn \tex_escapechar:D { 92 }
+      \__unravel_set_escapechar:n { 92 }
+      \tl_use:N \g__unravel_before_print_state_tl
       \int_compare:nNnT \g__unravel_noise_int > \c_zero
         {
           \exp_args:Nx \__unravel_print_state_output:n
@@ -4469,66 +4590,16 @@
   {
     \tl_if_empty:nF {#1}
       {
-        \int_set:Nn \l__unravel_print_int { \str_count:n {#1} }
         \__unravel_print_message:nn { <| ~ }
-          {
-            \int_compare:nNnTF
-              \l__unravel_print_int > \g__unravel_max_output_int
-              {
-                (
-                  \int_eval:n
-                    {
-                      \l__unravel_print_int
-                      - \g__unravel_max_output_int + 14
-                    } ~
-                  chars
-                )~
-                ...
-                \str_substr:nnn {#1}
-                  { \l__unravel_print_int - \g__unravel_max_output_int + 15 }
-                  { \l__unravel_print_int }
-              }
-              {#1}
-          }
+          { \__unravel_str_truncate_left:nn {#1} { \g__unravel_max_output_int } }
       }
   }
 \cs_new_protected:Npn \__unravel_print_state_prev:n #1
-  {
-    % \int_set:Nn \l__unravel_print_int { \str_count:n {#1} }
-    \__unravel_print_message:nn { || ~ } {#1}
-      % {
-      %   \int_compare:nNnTF \l__unravel_print_int > \g__unravel_max_prev_int
-      %     {
-      %       (
-      %         \int_eval:n
-      %           { \l__unravel_print_int - \g__unravel_max_prev_int + 14 } ~
-      %         chars
-      %       )~
-      %       ...
-      %       \str_substr:nnn {#1}
-      %         { \l__unravel_print_int - \g__unravel_max_prev_int + 15 }
-      %         { \l__unravel_print_int }
-      %     }
-      %     {#1}
-      % }
-  }
+  { \__unravel_print_message:nn { || ~ } {#1} }
 \cs_new_protected:Npn \__unravel_print_state_input:n #1
   {
-    \int_set:Nn \l__unravel_print_int { \str_count:n {#1} }
     \__unravel_print_message:nn { |> ~ }
-      {
-        \int_compare:nNnTF \l__unravel_print_int > \g__unravel_max_input_int
-          {
-            \str_substr:nnn {#1} { 1 } { \g__unravel_max_input_int - 14 }
-            ...~
-            (
-              \int_eval:n
-                { \l__unravel_print_int - \g__unravel_max_input_int + 14 } ~
-              chars
-            )
-          }
-          {#1}
-      }
+      { \__unravel_str_truncate_right:nn {#1} { \g__unravel_max_input_int } }
   }
 \cs_new_protected:Npn \__unravel_print_meaning:
   {
@@ -4546,21 +4617,20 @@
 \cs_new_protected:Npn \__unravel_print_action:
   {
     \int_gincr:N \g__unravel_step_int
-    \__unravel_print_message:nn { }
+    \__unravel_print:x
       {
-        % \\
-        [=====~ Step~ \int_use:N \g__unravel_step_int \ =====]~
+        [=====
+        \bool_if:NT \g__unravel_number_steps_bool
+          { ~ Step ~ \int_use:N \g__unravel_step_int \ }
+        =====]~
         \int_compare:nNnTF
           { \str_count:N \g__unravel_action_text_str }
           > { \g__unravel_max_action_int }
           {
-            \str_substr:Nnn \g__unravel_action_text_str
+            \str_range:Nnn \g__unravel_action_text_str
               { 1 } { \g__unravel_max_action_int - 3 } ...
           }
           { \g__unravel_action_text_str }
-        % \\
-        % \ \ < \int_use:N \g__unravel_input_int > % ^^A todo: remove
-        % \ < \seq_count:N \g__unravel_prev_input_seq > % ^^A todo: remove
       }
     \__unravel_print_state:
   }
@@ -4592,7 +4662,7 @@
         Set~ \exp_after:wN \token_to_str:N \l__unravel_defined_tl
         \tl_if_single:NT \l__unravel_defined_tl
           { ( \exp_after:wN \token_to_meaning:N \l__unravel_defined_tl ) }
-        = \exp_after:wN \tex_the:D \l__unravel_defined_tl
+        = \exp_after:wN \__unravel_the:w \l__unravel_defined_tl
       }
     \__unravel_omit_after_assignment:w
   }
@@ -4600,44 +4670,47 @@
   {
     \__unravel_print_message:nn { }
       {
-        \\
-        ========~ Welcome~ to~ the~ unravel~ package~ ========\\
-        \iow_indent:n
+        \bool_if:NTF \g__unravel_welcome_message_bool
           {
-            "<|"~ denotes~ the~ output~ to~ TeX's~ stomach. \\
-            "||"~ denotes~ tokens~ waiting~ to~ be~ used. \\
-            "|>"~ denotes~ tokens~ that~ we~ will~ act~ on. \\
-            Press~<enter>~to~continue;~'h'~<enter>~for~help. \\
+            \\
+            ========~ Welcome~ to~ the~ unravel~ package~ ========\\
+            \iow_indent:n
+              {
+                "<|"~ denotes~ the~ output~ to~ TeX's~ stomach. \\
+                "||"~ denotes~ tokens~ waiting~ to~ be~ used. \\
+                "|>"~ denotes~ tokens~ that~ we~ will~ act~ on. \\
+                Press~<enter>~to~continue;~'h'~<enter>~for~help. \\
+              }
           }
+          { [=====~Start~=====] }
       }
     \__unravel_print_state:
   }
 \cs_new_protected_nopar:Npn \__unravel_print_outcome:
-  {
-    % \int_gset_eq:NN \g__unravel_max_input_int \c_max_int
-    % \int_gset_eq:NN \g__unravel_max_prev_int \c_max_int
-    % \int_gset_eq:NN \g__unravel_max_output_int \c_max_int
-    % \__unravel_print_state:
-    \__unravel_print_message:nn { } { [=====~The~end!~=====] \\ }
-  }
+  { \__unravel_print:n { [=====~End~=====] } }
 \cs_new_protected_nopar:Npn \__unravel_prompt:
   {
     \int_gdecr:N \g__unravel_nonstop_int
     \int_compare:nNnF \g__unravel_nonstop_int > \c_zero
       {
         \group_begin:
-          \int_set_eq:NN \tex_escapechar:D \c_minus_one
+          \__unravel_set_escapechar:n { -1 }
           \int_set_eq:NN \tex_endlinechar:D \c_minus_one
-          \tl_use:N \g__unravel_prompt_before_tl
-          \tl_gclear:N \g__unravel_prompt_before_tl
+          \tl_use:N \g__unravel_before_prompt_tl
           \__unravel_prompt_aux:
         \group_end:
       }
   }
 \cs_new_protected_nopar:Npn \__unravel_prompt_aux:
   {
-    \ior_get_str:Nc \g__unravel_prompt_ior { Your~input }
-    \exp_args:Nv \__unravel_prompt_treat:n { Your~input }
+    \int_compare:nNnT { \etex_interactionmode:D } = { 3 }
+      {
+        \bool_if:NTF \g__unravel_explicit_prompt_bool
+          { \ior_get_str:Nc \c__unravel_prompt_ior }
+          { \ior_get_str:Nc \c__unravel_noprompt_ior }
+              { Your~input }
+        \exp_args:Nv \__unravel_prompt_treat:n { Your~input }
+      }
   }
 \cs_new_protected:Npn \__unravel_prompt_treat:n #1
   {
@@ -4669,6 +4742,9 @@
                   { \tl_gclear:N \g__unravel_tmpc_tl }
                 \group_insert_after:N \g__unravel_tmpc_tl
               }
+            { | } { \__unravel_prompt_scan_int:nn {#1}
+              \__unravel_prompt_vert:n }
+            { a } { \__unravel_prompt_all: }
           }
           { \__unravel_prompt_help: }
       }
@@ -4676,7 +4752,9 @@
 \cs_new_protected:Npn \__unravel_prompt_scan_int:nn #1
   {
     \tex_afterassignment:D \__unravel_prompt_scan_int_after:wn
-    \l__unravel_prompt_tmpa_int = 0 \use_none:n #1 \scan_stop:
+    \l__unravel_prompt_tmpa_int =
+      \tl_if_head_eq_charcode:fNF { \use_none:n #1 } - { 0 }
+      \use_ii:nn #1 \scan_stop:
   }
 \cs_new_protected:Npn \__unravel_prompt_scan_int_after:wn #1 \scan_stop: #2
   {
@@ -4686,44 +4764,159 @@
 \cs_new_protected:Npn \__unravel_prompt_help:
   {
     \__unravel_print:n { "m":~meaning~of~first~token }
-    \__unravel_print:n { "q":~semi-quiet }
-    \__unravel_print:n { "x":~exit~this~instance~of~unravel }
-    \__unravel_print:n { "X":~try~harder~to~exit }
+    \__unravel_print:n { "q":~semi-quiet~(same~as~"o1") }
+    \__unravel_print:n { "x"/"X":~exit~this~instance~of~unravel/TeX }
     \__unravel_print:n { "s<num>":~do~<num>~steps~silently }
     \__unravel_print:n
-      { "o<num>":~0~=>~only~log~not~online,~1~=>~both,~-1~=>~neither.}
-    \__unravel_print:n { "C<code>":~run~some~code~immediately }
+      { "o<num>":~1~=>~log~and~terminal,~0~=>~only~log,~-1~=>~neither.}
+    \__unravel_print:n { "C<code>":~run~some~expl3~code~immediately }
+    \__unravel_print:n { "|<num>":~silent~steps~until~<num>~fewer~"||" }
+    \__unravel_print:n { "a":~print~state~again,~without~truncating }
     \__unravel_prompt_aux:
   }
 \cs_new_protected:Npn \__unravel_prompt_silent_steps:n #1
   {
+    \int_compare:nNnF {#1} < \c_zero
+      {
+        \int_gset_eq:NN \g__unravel_noise_int \c_minus_one
+        \tl_gset:Nn \g__unravel_before_prompt_tl
+          {
+            \int_gset_eq:NN \g__unravel_noise_int \c_one
+            \tl_gclear:N \g__unravel_before_prompt_tl
+          }
+        \int_gset:Nn \g__unravel_nonstop_int {#1}
+      }
+  }
+\cs_new_protected:Npn \__unravel_prompt_vert:n #1
+  {
+    \int_compare:nNnTF {#1} < { 0 }
+      { \__unravel_prompt_vert:Nn > {#1} }
+      { \__unravel_prompt_vert:Nn < {#1} }
+  }
+\cs_new_protected:Npn \__unravel_prompt_vert:Nn #1#2
+  {
     \int_gset_eq:NN \g__unravel_noise_int \c_minus_one
-    \tl_gset:Nn \g__unravel_prompt_before_tl
-      { \int_gset_eq:NN \g__unravel_noise_int \c_one }
-    \int_gset:Nn \g__unravel_nonstop_int {#1}
+    \tl_gset:Nf \g__unravel_before_print_state_tl
+      {
+        \exp_args:NNf \exp_stop_f: \int_compare:nNnTF
+          { \int_eval:n { \seq_count:N \g__unravel_prev_input_seq - #2 } }
+          #1 { \seq_count:N \g__unravel_prev_input_seq }
+          {
+            \int_gset:Nn \g__unravel_nonstop_int
+              { \int_max:nn { \g__unravel_nonstop_int } { 2 } }
+          }
+          {
+            \int_gset_eq:NN \g__unravel_noise_int \c_one
+            \tl_gclear:N \g__unravel_before_print_state_tl
+          }
+      }
   }
-\cs_new_protected:Npn \unravel #1 { \__unravel_unravel:n {#1} }
-\cs_new_protected_nopar:Npn \UnravelDebug
+\cs_new_protected_nopar:Npn \__unravel_prompt_all:
   {
-    \bool_set_true:N \l__unravel_debug_bool
+    \tl_gset:Nx \g__unravel_tmpc_tl
+      {
+        \exp_not:n
+          {
+            \tl_gclear:N \g__unravel_tmpc_tl
+            \int_gset_eq:NN \g__unravel_max_output_int \c_max_int
+            \int_gset_eq:NN \g__unravel_max_input_int \c_max_int
+            \__unravel_print_state:
+          }
+        \__unravel_prompt_all_aux:N \g__unravel_max_output_int
+        \__unravel_prompt_all_aux:N \g__unravel_max_input_int
+      }
+    \group_insert_after:N \g__unravel_tmpc_tl
   }
-\cs_new_protected:Npn \__unravel_unravel:n #1
+\cs_new:Npn \__unravel_prompt_all_aux:N #1
+  { \exp_not:n { \int_gset:Nn #1 } { \int_use:N #1 } }
+\keys_define:nn { unravel/defaults }
+  {
+    explicit-prompt  .bool_gset:N = \g__unravel_default_explicit_prompt_bool ,
+    internal-debug   .bool_gset:N = \g__unravel_default_internal_debug_bool ,
+    max-action       .int_gset:N  = \g__unravel_default_max_action_int ,
+    max-output       .int_gset:N  = \g__unravel_default_max_output_int ,
+    max-input        .int_gset:N  = \g__unravel_default_max_input_int ,
+    number-steps     .bool_gset:N = \g__unravel_default_number_steps_bool ,
+    welcome-message  .bool_gset:N = \g__unravel_default_welcome_message_bool ,
+  }
+\keys_define:nn { unravel }
+  {
+    explicit-prompt  .bool_gset:N = \g__unravel_explicit_prompt_bool ,
+    internal-debug   .bool_gset:N = \g__unravel_internal_debug_bool ,
+    max-action       .int_gset:N  = \g__unravel_max_action_int ,
+    max-output       .int_gset:N  = \g__unravel_max_output_int ,
+    max-input        .int_gset:N  = \g__unravel_max_input_int ,
+    number-steps     .bool_gset:N = \g__unravel_number_steps_bool ,
+    welcome-message  .bool_gset:N = \g__unravel_welcome_message_bool ,
+  }
+\tl_map_inline:nn { { /defaults } { } }
+  {
+    \keys_define:nn { unravel #1 }
+      {
+        machine        .meta:nn =
+          { unravel #1 }
+          {
+            explicit-prompt = false ,
+            internal-debug  = false ,
+            max-action      = \c_max_int ,
+            max-output      = \c_max_int ,
+            max-input       = \c_max_int ,
+            number-steps    = false ,
+            welcome-message = false ,
+          } ,
+      }
+  }
+\NewDocumentCommand \unravel { O { } m } { \unravel:nn {#1} {#2} }
+\NewDocumentCommand \unravelsetup { m } { \unravel_setup:n {#1} }
+\cs_new_protected:Npn \unravel_setup:n #1
+  {
+    \keys_set:nn { unravel/defaults } {#1}
+    \keys_set:nn { unravel } {#1}
+  }
+\cs_new_protected:Npn \unravel:nn #1#2
+  {
+    \__unravel_init_key_vars:
+    \keys_set:nn { unravel } {#1}
+    \__unravel_init_vars:
+    \__unravel_input_gset:n {#2}
+    \__unravel_print_welcome:
+    \__unravel_main_loop:
+    \__unravel_exit_point:
+    \__unravel_print_outcome:
+    \__unravel_final_test:
+    \__unravel_exit_point:
+  }
+\cs_new_protected_nopar:Npn \__unravel_init_key_vars:
+  {
+    \bool_gset_eq:NN \g__unravel_explicit_prompt_bool \g__unravel_default_explicit_prompt_bool
+    \bool_gset_eq:NN \g__unravel_internal_debug_bool \g__unravel_default_internal_debug_bool
+    \bool_gset_eq:NN \g__unravel_number_steps_bool \g__unravel_default_number_steps_bool
+    \bool_gset_eq:NN \g__unravel_welcome_message_bool \g__unravel_default_welcome_message_bool
+    \int_gset_eq:NN \g__unravel_max_action_int \g__unravel_default_max_action_int
+    \int_gset_eq:NN \g__unravel_max_output_int \g__unravel_default_max_output_int
+    \int_gset_eq:NN \g__unravel_max_input_int  \g__unravel_default_max_input_int
+  }
+\cs_new_protected_nopar:Npn \__unravel_init_vars:
   {
-    \int_gzero:N  \g__unravel_step_int
-    \__unravel_input_gset:n {#1}
     \seq_gclear:N \g__unravel_prev_input_seq
     \gtl_gclear:N \g__unravel_output_gtl
+    \int_gzero:N  \g__unravel_step_int
     \tl_gclear:N  \g__unravel_if_limit_tl
     \int_gzero:N  \g__unravel_if_limit_int
     \int_gzero:N  \g__unravel_if_depth_int
     \gtl_gclear:N \g__unravel_after_assignment_gtl
     \bool_gset_true:N  \g__unravel_set_box_allowed_bool
     \bool_gset_false:N \g__unravel_name_in_progress_bool
-    \cs_gset_eq:NN \g__unravel_prompt_ior \c_minus_one % ^^A todo:?
-    \__unravel_print_welcome:
+  }
+\cs_new_protected_nopar:Npn \__unravel_main_loop:
+  {
+    \__unravel_get_x_next:
+    \__unravel_set_cmd:
+    \__unravel_do_step:
     \__unravel_main_loop:
-    \__unravel_exit_point:
-    \__unravel_print_outcome:
+  }
+\cs_new_protected_nopar:Npn \__unravel_final_test:
+  {
     \bool_if:nTF
       {
         \tl_if_empty_p:N \g__unravel_if_limit_tl
@@ -4731,22 +4924,14 @@
         && \int_compare_p:nNn \g__unravel_if_depth_int = \c_zero
         && \seq_if_empty_p:N \g__unravel_prev_input_seq
       }
-      { \__unravel_input_if_empty:TF { } { \__unravel_bad_finish: } }
-      { \__unravel_bad_finish: }
-    \__unravel_exit_point:
+      { \__unravel_input_if_empty:TF { } { \__unravel_final_bad: } }
+      { \__unravel_final_bad: }
   }
-\cs_new_protected_nopar:Npn \__unravel_bad_finish:
+\cs_new_protected_nopar:Npn \__unravel_final_bad:
   {
     \msg_error:nnx { unravel } { internal }
       { the-last-unravel-finished-badly }
   }
-\cs_new_protected_nopar:Npn \__unravel_main_loop:
-  {
-    \__unravel_get_x_next:
-    \__unravel_set_cmd:
-    \__unravel_do_step:
-    \__unravel_main_loop:
-  }
 \msg_new:nnn { unravel } { unknown-primitive }
   { Internal~error:~the~primitive~'#1'~is~not~known. }
 \msg_new:nnn { unravel } { extra-fi-or-else }
@@ -4804,14 +4989,21 @@
   { Missing~\iow_char:N\\endcsname~inserted. }
 \msg_new:nnn { unravel } { runaway-if }
   { Runaway~\iow_char:N\\if... }
+\msg_new:nnn { unravel } { runaway-macro-parameter }
+  {
+    Runaway~macro~parameter~\# #2~after \\\\
+    \iow_indent:n {#1}
+  }
 \msg_new:nnn { unravel } { extra-or }
   { Extra~\iow_char:N\\or. }
 \msg_new:nnn { unravel } { missing-equals }
   { Missing~equals~for~\iow_char:N\\ifnum~or~\iow_char:N\\ifdim. }
 \msg_new:nnn { unravel } { internal }
-  { Internal~error:~'#1'.~\ Please report. }
+  { Internal~error:~'#1'.~\ Please~report. }
 \msg_new:nnn { unravel } { not-implemented }
   { The~following~feature~is~not~implemented:~'#1'. }
+\msg_new:nnn { unravel } { endinput-ignored }
+  { The~primitive~\iow_char:N\\endinput~was~ignored. }
 %% 
 %%
 %% End of file `unravel.sty'.