%%
%% This is file `l3str.sty',
%% generated with the docstrip utility.
%%
%% The original source files were:
%%
%% l3str.dtx  (with options: `package')
%% 
%% EXPERIMENTAL CODE
%% 
%% Do not distribute this file without also distributing the
%% source files specified above.
%% 
%% Do not distribute a modified version of this file.
%% 
%% File: l3str.dtx Copyright (C) 2011-2012 The LaTeX3 Project
%%
%% It may be distributed and/or modified under the conditions of the
%% LaTeX Project Public License (LPPL), either version 1.3c of this
%% license or (at your option) any later version.  The latest version
%% of this license is in the file
%%
%%    http://www.latex-project.org/lppl.txt
%%
%% This file is part of the "l3experimental bundle" (The Work in LPPL)
%% and all files in that bundle must be distributed together.
%%
%% The released version of this bundle is available from CTAN.
%%
%% -----------------------------------------------------------------------
%%
%% The development version of the bundle can be found at
%%
%%    http://www.latex-project.org/svnroot/experimental/trunk/
%%
%% for those people who are interested.
%%
%%%%%%%%%%%
%% NOTE: %%
%%%%%%%%%%%
%%
%%   Snapshots taken from the repository represent work in progress and may
%%   not work or may contain conflicting material!  We therefore ask
%%   people _not_ to put them into distributions, archives, etc. without
%%   prior consultation with the LaTeX3 Project.
%%
%% -----------------------------------------------------------------------
\RequirePackage{expl3}
\GetIdInfo$Id: l3str.dtx 4339 2012-11-24 19:16:43Z joseph $
  {L3 Experimental strings}
\ProvidesExplPackage
  {\ExplFileName}{\ExplFileDate}{\ExplFileVersion}{\ExplFileDescription}
\RequirePackage{l3tl-analysis,l3tl-build,l3flag}
\cs_if_exist:NF \use_ii_i:nn
  { \cs_new:Npn \use_ii_i:nn #1#2 { #2 #1 } }
\cs_new_eq:NN \str_new:N \tl_new:N
\cs_generate_variant:Nn \str_new:N { c }
\tl_map_inline:nn
  {
    { set }
    { gset }
    { const }
    { put_left }
    { gput_left }
    { put_right }
    { gput_right }
  }
  {
    \cs_new_protected:cpx { str_ #1 :Nn } ##1##2
      { \exp_not:c { tl_ #1 :Nx } ##1 { \exp_not:N \tl_to_str:n {##2} } }
    \exp_args:Nc \cs_generate_variant:Nn { str_ #1 :Nn } { Nx , cn , cx }
  }
\cs_new_protected_nopar:Npn \__str_tmp:w { }
\tl_new:N \l__str_internal_tl
\int_new:N \l__str_internal_int
\tl_new:N \g__str_result_tl
\int_const:Nn \c_forty_eight  { 48 }
\int_const:Nn \c_fifty_eight  { 58 }
\int_const:Nn \c_sixty_five   { 65 }
\int_const:Nn \c_ninety_one   { 91 }
\int_const:Nn \c_ninety_seven { 97 }
\int_const:Nn \c_one_hundred_twenty_three { 123 }
\int_const:Nn \c_one_hundred_twenty_seven { 127 }
\int_const:Nn \c_max_char_int
  { \pdftex_if_engine:TF { "FF } { "10FFFF } }
\int_const:Nn \c__str_replacement_char_int { "FFFD }
\tl_const:Nx \c_backslash_str { \cs_to_str:N \\ }
\tl_const:Nx \c_lbrace_str    { \cs_to_str:N \{ }
\tl_const:Nx \c_rbrace_str    { \cs_to_str:N \} }
\tl_const:Nx \c_hash_str      { \cs_to_str:N \# }
\tl_const:Nx \c_tilde_str     { \cs_to_str:N \~ }
\tl_const:Nx \c_percent_str   { \cs_to_str:N \% }
\prop_new:N \g__str_alias_prop
\prop_gput:Nnn \g__str_alias_prop { latin1 } { iso88591 }
\prop_gput:Nnn \g__str_alias_prop { latin2 } { iso88592 }
\prop_gput:Nnn \g__str_alias_prop { latin3 } { iso88593 }
\prop_gput:Nnn \g__str_alias_prop { latin4 } { iso88594 }
\prop_gput:Nnn \g__str_alias_prop { latin5 } { iso88599 }
\prop_gput:Nnn \g__str_alias_prop { latin6 } { iso885910 }
\prop_gput:Nnn \g__str_alias_prop { latin7 } { iso885913 }
\prop_gput:Nnn \g__str_alias_prop { latin8 } { iso885914 }
\prop_gput:Nnn \g__str_alias_prop { latin9 } { iso885915 }
\prop_gput:Nnn \g__str_alias_prop { latin10 } { iso885916 }
\prop_gput:Nnn \g__str_alias_prop { utf16le } { utf16 }
\prop_gput:Nnn \g__str_alias_prop { utf16be } { utf16 }
\prop_gput:Nnn \g__str_alias_prop { utf32le } { utf32 }
\prop_gput:Nnn \g__str_alias_prop { utf32be } { utf32 }
\prop_gput:Nnn \g__str_alias_prop { hexadecimal } { hex }
\bool_new:N \g__str_error_bool
\flag_new:n { str_byte }
\flag_new:n { str_error }
\group_begin:
\char_set_lccode:nn { `\* } { `\  }
\char_set_lccode:nn { `\A } { `\A }
\tl_to_lowercase:n
  {
    \group_end:
    \cs_new:Npn \__str_to_other:n #1
      {
        \exp_after:wN \__str_to_other_loop:w \tl_to_str:n {#1} ~ %
        A ~ A ~ A ~ A ~ A ~ A ~ A ~ A ~ \q_mark \q_stop
      }
    \cs_new:Npn \__str_to_other_loop:w
      #1 ~ #2 ~ #3 ~ #4 ~ #5 ~ #6 ~ #7 ~ #8 ~ #9 \q_stop
      {
        \if_meaning:w A #8
          \__str_to_other_end:w
        \fi:
        \__str_to_other_loop:w
        #9 #1 * #2 * #3 * #4 * #5 * #6 * #7 * #8 * \q_stop
      }
    \cs_new:Npn \__str_to_other_end:w \fi: #1 \q_mark #2 * A #3 \q_stop
      { \fi: #2 }
  }
\group_begin:
\char_set_lccode:nn { `\* } { `\  }
\char_set_lccode:nn { `\A } { `\A }
\tl_to_lowercase:n
  {
    \group_end:
    \cs_new_protected:Npn \__str_gset_other:Nn #1#2
      {
        \tl_gset:Nx #1
          {
            \exp_after:wN \__str_gset_other_loop:w \tl_to_str:n {#2} ~ %
            A ~ A ~ A ~ A ~ A ~ A ~ A ~ A ~ A ~ \q_stop
          }
      }
    \cs_new:Npn \__str_gset_other_loop:w
      #1 ~ #2 ~ #3 ~ #4 ~ #5 ~ #6 ~ #7 ~ #8 ~ #9 ~
      {
        \if_meaning:w A #9
          \__str_gset_other_end:w
        \fi:
        #1 * #2 * #3 * #4 * #5 * #6 * #7 * #8 * #9
        \__str_gset_other_loop:w *
      }
    \cs_new:Npn \__str_gset_other_end:w \fi: #1 * A #2 \q_stop
      { \fi: #1 }
  }
\cs_new:Npn \str_count_spaces:N
  { \exp_args:No \str_count_spaces:n }
\cs_new:Npn \str_count_spaces:n #1
  {
    \int_eval:n
      {
        \exp_after:wN \__str_count_spaces_loop:wwwwwwwww
        \tl_to_str:n {#1} ~
        X 7 ~ X 6 ~ X 5 ~ X 4 ~ X 3 ~ X 2 ~ X 1 ~ X 0 ~ X -1 ~
        \q_stop
      }
  }
\cs_new:Npn \__str_count_spaces_loop:wwwwwwwww #1~#2~#3~#4~#5~#6~#7~#8~#9~
  {
    \if_meaning:w X #9
      \exp_after:wN \use_none_delimit_by_q_stop:w
    \fi:
    \c_nine + \__str_count_spaces_loop:wwwwwwwww
  }
\cs_new_nopar:Npn \str_count:N { \exp_args:No \str_count:n }
\cs_new:Npn \str_count:n #1
  {
    \__str_count:n
      {
        \str_count_spaces:n {#1}
        + \exp_after:wN \__str_count_loop:NNNNNNNNN \tl_to_str:n {#1}
      }
  }
\cs_new:Npn \__str_count_unsafe:n #1
  {
    \__str_count:n
      { \__str_count_loop:NNNNNNNNN #1 }
  }
\cs_new:Npn \str_count_ignore_spaces:n #1
  {
    \__str_count:n
      { \exp_after:wN \__str_count_loop:NNNNNNNNN \tl_to_str:n {#1} }
  }
\cs_new:Npn \__str_count:n #1
  {
    \int_eval:n
      {
        #1
        { X \c_eight } { X \c_seven } { X \c_six   }
        { X \c_five  } { X \c_four  } { X \c_three }
        { X \c_two   } { X \c_one   } { X \c_zero  }
        \q_stop
      }
  }
\cs_set:Npn \__str_count_loop:NNNNNNNNN #1#2#3#4#5#6#7#8#9
  {
    \if_meaning:w X #9
      \exp_after:wN \use_none_delimit_by_q_stop:w
    \fi:
    \c_nine + \__str_count_loop:NNNNNNNNN
  }
\cs_new_nopar:Npn \str_head:N { \exp_args:No \str_head:n }
\cs_set:Npn \str_head:n #1
  {
    \exp_after:wN \__str_head:w
    \tl_to_str:n {#1}
    { { } } ~ \q_stop
  }
\cs_set:Npn \__str_head:w #1 ~ %
  { \use_i_delimit_by_q_stop:nw #1 { ~ } }
\cs_new:Npn \str_head_ignore_spaces:n #1
  {
    \exp_after:wN \use_i_delimit_by_q_stop:nw
    \tl_to_str:n {#1} { } \q_stop
  }
\cs_new_nopar:Npn \str_tail:N { \exp_args:No \str_tail:n }
\cs_set:Npn \str_tail:n #1
  {
    \exp_after:wN \__str_tail_auxi:w
    \reverse_if:N \if_charcode:w
        \scan_stop: \tl_to_str:n {#1} X X \q_stop
  }
\cs_set:Npn \__str_tail_auxi:w #1 X #2 \q_stop { \fi: #1 }
\cs_new:Npn \str_tail_ignore_spaces:n #1
  {
    \exp_after:wN \__str_tail_auxii:w
    \tl_to_str:n {#1} X X \q_stop
  }
\cs_new:Npn \__str_tail_auxii:w #1 #2 X #3 \q_stop { #2 }
\cs_new:Npn \__str_skip_c_zero:w #1;
  {
    \if_int_compare:w \__int_eval:w #1 > \c_eight
      \exp_after:wN \__str_skip_loop:wNNNNNNNN
    \else:
      \exp_after:wN \__str_skip_end:w
      \int_use:N \__int_eval:w
    \fi:
    #1 ;
  }
\cs_new:Npn \__str_skip_loop:wNNNNNNNN #1; #2#3#4#5#6#7#8#9
  { \exp_after:wN \__str_skip_c_zero:w \int_use:N \__int_eval:w #1 - \c_eight ; }
\cs_new:Npn \__str_skip_end:w #1 ;
  {
    \exp_after:wN \__str_skip_end:NNNNNNNN
    \if_case:w \if_int_compare:w #1 > \c_zero #1 \else: 0 \fi: \exp_stop_f:
    \or: \or: \or: \or: \or: \or: \or: \or:
  }
\cs_new:Npn \__str_skip_end:NNNNNNNN #1#2#3#4#5#6#7#8 { \fi: \c_zero }
\cs_new:Npn \__str_collect_delimit_by_q_stop:w #1;
  {
    \exp_after:wN \__str_collect_loop:wn
    \int_use:N \__int_eval:w #1 ;
    { }
  }
\cs_new:Npn \__str_collect_loop:wn #1 ;
  {
    \if_int_compare:w #1 > \c_seven
      \exp_after:wN \__str_collect_loop:wnNNNNNNN
    \else:
      \exp_after:wN \__str_collect_end:wn
    \fi:
    #1 ;
  }
\cs_new:Npn \__str_collect_loop:wnNNNNNNN #1; #2 #3#4#5#6#7#8#9
  {
    \exp_after:wN \__str_collect_loop:wn
    \int_use:N \__int_eval:w #1 - \c_seven ;
    { #2 #3#4#5#6#7#8#9 }
  }
\cs_new:Npn \__str_collect_end:wn #1 ;
  {
    \exp_after:wN \__str_collect_end:nnnnnnnnw
    \if_case:w \if_int_compare:w #1 > \c_zero #1 \else: 0 \fi: \exp_stop_f:
    \or: \or: \or: \or: \or: \or: \fi:
  }
\cs_new:Npn \__str_collect_end:nnnnnnnnw #1#2#3#4#5#6#7#8 #9 \q_stop
  { #1#2#3#4#5#6#7#8 }
\cs_new_nopar:Npn \str_item:Nn { \exp_args:No \str_item:nn }
\cs_new:Npn \str_item:nn #1#2
  {
    \exp_args:Nf \tl_to_str:n
      {
        \exp_args:Nf \__str_item_unsafe:nn
          { \__str_to_other:n {#1} } {#2}
      }
  }
\cs_new:Npn \str_item_ignore_spaces:nn #1
  { \exp_args:No \__str_item_unsafe:nn { \tl_to_str:n {#1} } }
\cs_new:Npn \__str_item_unsafe:nn #1#2
  {
    \exp_after:wN \__str_item:ww
    \int_use:N \__int_eval:w #2 \exp_after:wN ;
    \__int_value:w \__str_count_unsafe:n {#1} ;
      { } #1
    \q_stop
  }
\cs_new:Npn \__str_item:ww #1; #2;
  {
    \int_compare:nNnTF {#1} < \c_zero
      {
        \int_compare:nNnTF {#1} < {-#2}
          { \use_none_delimit_by_q_stop:w }
          {
            \exp_after:wN \use_i_delimit_by_q_stop:nw
            \tex_romannumeral:D \__str_skip_c_zero:w #1 + #2 + \c_one ;
          }
      }
      {
        \int_compare:nNnTF {#1} > {#2}
          { \use_none_delimit_by_q_stop:w }
          {
            \exp_after:wN \use_i_delimit_by_q_stop:nw
            \tex_romannumeral:D \__str_skip_c_zero:w #1 ;
          }
      }
  }
\cs_new_nopar:Npn \str_substr:Nnn { \exp_args:No \str_substr:nnn }
\cs_new:Npn \str_substr:nnn #1#2#3
  {
    \exp_args:Nf \tl_to_str:n
      {
        \exp_args:Nf \__str_substr_unsafe:nnn
          { \__str_to_other:n {#1} } {#2} {#3}
      }
  }
\cs_new:Npn \str_substr_ignore_spaces:nnn #1
  { \exp_args:No \__str_substr_unsafe:nnn { \tl_to_str:n {#1} } }
\cs_new:Npn \__str_substr_unsafe:nnn #1#2#3
  {
    \exp_after:wN \__str_substr:www
    \__int_value:w \__str_count_unsafe:n {#1} \exp_after:wN ;
    \int_use:N \__int_eval:w #2 + \c_zero \exp_after:wN ;
    \int_use:N \__int_eval:w
      \exp_args:Nf \__str_substr:nN {#3} \c_max_int ;
      { } #1
    \q_stop
  }
\cs_new:Npn \__str_substr:nN #1 #2
  { \tl_if_empty:nTF {#1} {#2} {#1} }
\cs_new:Npn \__str_substr:www #1; #2; #3;
  {
    \exp_args:Nf \__str_substr:nnw
      { \__str_substr_normalize_range:nn {#2} {#1} }
      { \__str_substr_normalize_range:nn {#3} {#1} }
  }
\cs_new:Npn \__str_substr:nnw #1#2
  {
    \exp_after:wN \__str_collect_delimit_by_q_stop:w
    \int_use:N \__int_eval:w #2 + \c_one - #1 \exp_after:wN ;
    \tex_romannumeral:D \__str_skip_c_zero:w #1 ;
  }
\cs_new:Npn \__str_substr_normalize_range:nn #1#2
  {
    \int_eval:n
      {
        \if_int_compare:w #1 < \c_zero
          \if_int_compare:w #1 < - #2 \exp_stop_f:
            \c_zero
          \else:
            #1 + #2 + \c_one
          \fi:
        \else:
          \if_int_compare:w #1 > #2 \exp_stop_f:
            #2
          \else:
            #1
          \fi:
        \fi:
      }
  }
\prg_new_conditional:Npnn \str_if_eq:NN #1#2 { p , TF , T , F }
  {
    \if_int_compare:w \pdftex_strcmp:D { \tl_to_str:N #1 } { \tl_to_str:N #2 }
      = \c_zero \prg_return_true: \else: \prg_return_false: \fi:
  }
\prg_new_conditional:Npnn \__str_if_contains_char:NN #1#2 { T , TF }
  {
    \exp_after:wN \__str_if_contains_char_aux:NN \exp_after:wN #2
      #1 { \__prg_break:n { ? \fi: } }
    \__prg_break_point:
    \prg_return_false:
  }
\prg_new_conditional:Npnn \__str_if_contains_char:nN #1#2 { TF }
  {
    \__str_if_contains_char_aux:NN #2 #1 { \__prg_break:n { ? \fi: } }
    \__prg_break_point:
    \prg_return_false:
  }
\cs_new:Npn \__str_if_contains_char_aux:NN #1#2
  {
    \if_charcode:w #1 #2
      \exp_after:wN \__str_if_contains_char_true:
    \fi:
    \__str_if_contains_char_aux:NN #1
  }
\cs_new_nopar:Npn \__str_if_contains_char_true:
  { \__prg_break:n { \prg_return_true: \use_none:n } }
\prg_new_conditional:Npnn \__str_octal_use:N #1 { TF }
  {
    \if_int_compare:w \c_one < '1 \token_to_str:N #1 \exp_stop_f:
      #1 \prg_return_true:
    \else:
      \prg_return_false:
    \fi:
  }
\prg_new_conditional:Npnn \__str_hexadecimal_use:N #1 { TF }
  {
    \if_int_compare:w \c_two < "1 \token_to_str:N #1 \exp_stop_f:
      #1 \prg_return_true:
    \else:
      \if_case:w \__int_eval:w
          \exp_after:wN ` \token_to_str:N #1 - `a
        \__int_eval_end:
           A
      \or: B
      \or: C
      \or: D
      \or: E
      \or: F
      \else:
        \prg_return_false:
        \exp_after:wN \use_none:n
      \fi:
      \prg_return_true:
    \fi:
  }
\cs_new_eq:NN \str_show:n \tl_show:n
\cs_new_eq:NN \str_show:N \tl_show:N
\cs_generate_variant:Nn \str_show:N { c }
\group_begin:
  \char_set_catcode_other:n { \c_zero }
  \tl_set:Nx \l__str_internal_tl { \tl_to_str:n { 0123456789ABCDEF } }
  \exp_args:No \tl_map_inline:nn { \l__str_internal_tl " }
    { \char_set_lccode:nn {`#1} { \c_zero } }
  \tl_map_inline:Nn \l__str_internal_tl
    {
      \tl_map_inline:Nn \l__str_internal_tl
        {
          \char_set_lccode:nn { \c_zero } {"#1##1}
          \tl_to_lowercase:n
            {
              \tl_const:cx
                { c__str_byte_ \int_eval:n {"#1##1} _tl }
                { ^^@ #1 ##1 }
            }
        }
    }
\group_end:
\tl_const:cn { c__str_byte_-1_tl } { { } \use_none:n { } }
\cs_new:Npn \__str_output_byte:n #1
  { \__str_output_byte:w #1 \__str_output_end: }
\cs_new_nopar:Npn \__str_output_byte:w
  {
    \exp_after:wN \exp_after:wN
    \exp_after:wN \use_i:nnn
    \cs:w c__str_byte_ \int_use:N \__int_eval:w
  }
\cs_new:Npn \__str_output_hexadecimal:n #1
  { \__str_output_hexadecimal:w #1 \__str_output_end: }
\cs_new_nopar:Npn \__str_output_hexadecimal:w
  {
    \exp_after:wN \exp_after:wN
    \exp_after:wN \use_none:n
    \cs:w c__str_byte_ \int_use:N \__int_eval:w
  }
\cs_new_nopar:Npn \__str_output_end:
  { \__int_eval_end: _tl \cs_end: }
\cs_new:Npn \__str_output_byte_pair_be:n #1
  {
    \exp_args:Nf \__str_output_byte_pair:nnN
      { \int_div_truncate:nn { #1 } { "100 } } {#1} \use:nn
  }
\cs_new:Npn \__str_output_byte_pair_le:n #1
  {
    \exp_args:Nf \__str_output_byte_pair:nnN
      { \int_div_truncate:nn { #1 } { "100 } } {#1} \use_ii_i:nn
  }
\cs_new:Npn \__str_output_byte_pair:nnN #1#2#3
  {
    #3
      { \__str_output_byte:n { #1 } }
      { \__str_output_byte:n { #2 - #1 * "100 } }
  }
\cs_new_protected:Npn \__str_convert_gmap:N #1
  {
    \tl_gset:Nx \g__str_result_tl
      {
        \exp_after:wN \__str_convert_gmap_loop:NN
        \exp_after:wN #1
          \g__str_result_tl { ? \__prg_break: }
        \__prg_break_point:
      }
  }
\cs_new:Npn \__str_convert_gmap_loop:NN #1#2
  {
    \use_none:n #2
    #1#2
    \__str_convert_gmap_loop:NN #1
  }
\cs_new_protected:Npn \__str_convert_gmap_internal:N #1
  {
    \tl_gset:Nx \g__str_result_tl
      {
        \exp_after:wN \__str_convert_gmap_internal_loop:Nww
        \exp_after:wN #1
          \g__str_result_tl \s__tl \q_stop \__prg_break: \s__tl
        \__prg_break_point:
      }
  }
\cs_new:Npn \__str_convert_gmap_internal_loop:Nww #1 #2 \s__tl #3 \s__tl
  {
    \use_none_delimit_by_q_stop:w #3 \q_stop
    #1 {#3}
    \__str_convert_gmap_internal_loop:Nww #1
  }
\cs_new_protected:Npn \__str_if_flag_error:nnx #1
  {
    \flag_if_raised:nTF {#1}
      { \__msg_kernel_error:nnx { str } }
      { \use_none:nn }
  }
\cs_new_protected:Npn \__str_if_flag_no_error:nnx #1#2#3
  { \flag_if_raised:nT {#1} { \bool_gset_true:N \g__str_error_bool } }
\cs_new_protected:Npn \__str_if_flag_times:nT #1#2
  { \flag_if_raised:nT {#1} { #2~(x \flag_height:n {#1} ) } }
\cs_new_protected_nopar:Npn \str_set_convert:Nnnn
  { \__str_convert:nNNnnn { } \tl_set_eq:NN }
\cs_new_protected_nopar:Npn \str_gset_convert:Nnnn
  { \__str_convert:nNNnnn { } \tl_gset_eq:NN }
\prg_new_protected_conditional:Npnn
    \str_set_convert:Nnnn #1#2#3#4 { T , F , TF }
  {
    \bool_gset_false:N \g__str_error_bool
    \__str_convert:nNNnnn
      { \cs_set_eq:NN \__str_if_flag_error:nnx \__str_if_flag_no_error:nnx }
      \tl_set_eq:NN #1 {#2} {#3} {#4}
    \bool_if:NTF \g__str_error_bool \prg_return_false: \prg_return_true:
  }
\prg_new_protected_conditional:Npnn
    \str_gset_convert:Nnnn #1#2#3#4 { T , F , TF }
  {
    \bool_gset_false:N \g__str_error_bool
    \__str_convert:nNNnnn
      { \cs_set_eq:NN \__str_if_flag_error:nnx \__str_if_flag_no_error:nnx }
      \tl_gset_eq:NN #1 {#2} {#3} {#4}
    \bool_if:NTF \g__str_error_bool \prg_return_false: \prg_return_true:
  }
\cs_new_protected:Npn \__str_convert:nNNnnn #1#2#3#4#5#6
  {
    \group_begin:
      #1
      \__str_gset_other:Nn \g__str_result_tl {#4}
      \exp_after:wN \__str_convert:wwwnn
        \tl_to_str:n {#5} /// \q_stop
        { decode } { unescape }
        \prg_do_nothing:
        \__str_convert_decode_:
      \exp_after:wN \__str_convert:wwwnn
        \tl_to_str:n {#6} /// \q_stop
        { encode } { escape }
        \use_ii_i:nn
        \__str_convert_encode_:
    \group_end:
    #2 #3 \g__str_result_tl
  }
\cs_new_protected:Npn \__str_convert:wwwnn
    #1 / #2 // #3 \q_stop #4#5
  {
    \__str_convert:nnn {enc} {#4} {#1}
    \__str_convert:nnn {esc} {#5} {#2}
    \exp_args:Ncc \__str_convert:NNnNN
      { __str_convert_#4_#1: } { __str_convert_#5_#2: } {#2}
  }
\cs_new_protected:Npn \__str_convert:NNnNN #1#2#3#4#5
  {
    \if_meaning:w #1 #5
      \tl_if_empty:nF {#3}
        { \__msg_kernel_error:nnx { str } { native-escaping } {#3} }
      #1
    \else:
      #4 #2 #1
    \fi:
  }
\cs_new_protected:Npn \__str_convert:nnn #1#2#3
  {
    \cs_if_exist:cF { __str_convert_#2_#3: }
      {
        \exp_args:Nx \__str_convert:nnnn
          { \__str_convert_lowercase_alphanum:n {#3} }
          {#1} {#2} {#3}
      }
  }
\cs_new_protected:Npn \__str_convert:nnnn #1#2#3#4
  {
    \cs_if_exist:cF { __str_convert_#3_#1: }
      {
        \prop_get:NnNF \g__str_alias_prop {#1} \l__str_internal_tl
          { \tl_set:Nn \l__str_internal_tl {#1} }
        \cs_if_exist:cF { __str_convert_#3_ \l__str_internal_tl : }
          {
            \file_if_exist:nTF { l3str-#2- \l__str_internal_tl .def }
              {
                \group_begin:
                  \__str_load_catcodes:
                  \file_input:n { l3str-#2- \l__str_internal_tl .def }
                \group_end:
              }
              {
                \tl_clear:N \l__str_internal_tl
                \__msg_kernel_error:nnxx { str } { unknown-#2 } {#4} {#1}
              }
          }
        \cs_if_exist:cF { __str_convert_#3_#1: }
          {
            \cs_gset_eq:cc { __str_convert_#3_#1: }
              { __str_convert_#3_ \l__str_internal_tl : }
          }
      }
    \cs_gset_eq:cc { __str_convert_#3_#4: } { __str_convert_#3_#1: }
  }
\cs_new:Npn \__str_convert_lowercase_alphanum:n #1
  {
    \exp_after:wN \__str_convert_lowercase_alphanum_loop:N
      \tl_to_str:n {#1} { ? \__prg_break: }
    \__prg_break_point:
  }
\cs_new:Npn \__str_convert_lowercase_alphanum_loop:N #1
  {
    \use_none:n #1
    \if_int_compare:w `#1 < \c_ninety_one
      \if_int_compare:w `#1 < \c_sixty_five
        \if_int_compare:w \c_one < 1#1 \exp_stop_f:
          #1
        \fi:
      \else:
        \__str_output_byte:n { `#1 + \c_thirty_two }
      \fi:
    \else:
      \if_int_compare:w `#1 < \c_one_hundred_twenty_three
        \if_int_compare:w `#1 < \c_ninety_seven
        \else:
          #1
        \fi:
      \fi:
    \fi:
    \__str_convert_lowercase_alphanum_loop:N
  }
\cs_new_protected:Npn \__str_load_catcodes:
  {
    \char_set_catcode_escape:N \\
    \char_set_catcode_group_begin:N \{
    \char_set_catcode_group_end:N \}
    \char_set_catcode_math_toggle:N \$
    \char_set_catcode_alignment:N \&
    \char_set_catcode_parameter:N \#
    \char_set_catcode_math_superscript:N \^
    \char_set_catcode_ignore:N \ %
    \char_set_catcode_space:N \~
    \tl_map_function:nN { abcdefghijklmnopqrstuvwxyz_:ABCDEFILNPSTUX }
      \char_set_catcode_letter:N
    \tl_map_function:nN { 0123456789"'?*+-.(),`!/<>[];= }
      \char_set_catcode_other:N
    \char_set_catcode_comment:N \%
    \int_set:Nn \tex_endlinechar:D {32}
  }
\pdftex_if_engine:TF
  { \cs_new_eq:NN \__str_filter_bytes:n \use:n }
  {
    \cs_new:Npn \__str_filter_bytes:n #1
      {
        \__str_filter_bytes_aux:N #1
          { ? \__prg_break: }
        \__prg_break_point:
      }
    \cs_new:Npn \__str_filter_bytes_aux:N #1
      {
        \use_none:n #1
        \if_int_compare:w `#1 < 256 \exp_stop_f:
          #1
        \else:
          \flag_raise:n { str_byte }
        \fi:
        \__str_filter_bytes_aux:N
      }
  }
\pdftex_if_engine:TF
  { \cs_new_protected_nopar:Npn \__str_convert_unescape_: { } }
  {
    \cs_new_protected_nopar:Npn \__str_convert_unescape_:
      {
        \flag_clear:n { str_byte }
        \tl_gset:Nx \g__str_result_tl
          { \exp_args:No \__str_filter_bytes:n \g__str_result_tl }
        \__str_if_flag_error:nnx { str_byte } { non-byte } { bytes }
      }
  }
\cs_new_eq:NN \__str_convert_unescape_bytes: \__str_convert_unescape_:
\cs_new_protected_nopar:Npn \__str_convert_escape_: { }
\cs_new_eq:NN \__str_convert_escape_bytes: \__str_convert_escape_:
\cs_new_protected_nopar:Npn \__str_convert_decode_:
  { \__str_convert_gmap:N \__str_decode_native_char:N }
\cs_new:Npn \__str_decode_native_char:N #1
  { #1 \s__tl \__int_value:w `#1 \s__tl }
\group_begin:
  \char_set_catcode_other:n { 0 }
  \pdftex_if_engine:TF
    {
      \cs_new_protected_nopar:Npn \__str_convert_encode_:
        {
          \flag_clear:n { str_error }
          \__str_convert_gmap_internal:N \__str_encode_native_char:n
          \__str_if_flag_error:nnx { str_error }
            { pdfTeX-native-overflow } { }
        }
      \cs_new:Npn \__str_encode_native_char:n #1
        {
          \if_int_compare:w #1 < \c_two_hundred_fifty_six
            \__str_output_byte:n {#1}
          \else:
            \flag_raise:n { str_error }
            ?
          \fi:
        }
      \__msg_kernel_new:nnnn { str } { pdfTeX-native-overflow }
        { Character~code~too~large~for~pdfTeX. }
        {
          The~pdfTeX~engine~only~supports~8-bit~characters:~
          valid~character~codes~are~in~the~range~[0,255].~
          To~manipulate~arbitrary~Unicode,~use~LuaTeX~or~XeTeX.
        }
    }
    {
      \cs_new_protected_nopar:Npn \__str_convert_encode_:
        {
          \int_zero:N \l__tl_build_offset_int
          \__tl_gbuild_x:Nw \g__str_result_tl
            \exp_after:wN \__str_encode_native_loop:w
              \g__str_result_tl \s__tl { \q_stop \__prg_break: } \s__tl
            \__prg_break_point:
          \__tl_build_end:
        }
      \cs_new_protected:Npn \__str_encode_native_loop:w #1 \s__tl #2 \s__tl
        {
          \use_none_delimit_by_q_stop:w #2 \q_stop
          \tex_lccode:D \l__str_internal_int \__int_eval:w #2 \__int_eval_end:
          \tl_to_lowercase:n { \__tl_build_one:n { ^^@ } }
          \__str_encode_native_loop:w
        }
    }
\group_end:
\cs_new_protected:Npn \__str_declare_eight_bit_encoding:nnn #1#2#3
  {
    \tl_set:Nn \l__str_internal_tl {#1}
    \cs_new_protected_nopar:cpn { __str_convert_decode_#1: }
      { \__str_convert_decode_eight_bit:n {#1} }
    \cs_new_protected_nopar:cpn { __str_convert_encode_#1: }
      { \__str_convert_encode_eight_bit:n {#1} }
    \tl_const:cn { c__str_encoding_#1_tl } {#2}
    \tl_const:cn { c__str_encoding_#1_missing_tl } {#3}
  }
\cs_new_protected:Npn \__str_convert_decode_eight_bit:n #1
  {
    \group_begin:
      \int_zero:N \l__str_internal_int
      \exp_last_unbraced:Nx \__str_decode_eight_bit_load:nn
        { \tl_use:c { c__str_encoding_#1_tl } }
        { \q_stop \__prg_break: } { }
      \__prg_break_point:
      \exp_last_unbraced:Nx \__str_decode_eight_bit_load_missing:n
        { \tl_use:c { c__str_encoding_#1_missing_tl } }
        { \q_stop \__prg_break: }
      \__prg_break_point:
      \flag_clear:n { str_error }
      \__str_convert_gmap:N \__str_decode_eight_bit_char:N
      \__str_if_flag_error:nnx { str_error } { decode-8-bit } {#1}
    \group_end:
  }
\cs_new_protected:Npn \__str_decode_eight_bit_load:nn #1#2
  {
    \use_none_delimit_by_q_stop:w #1 \q_stop
    \tex_dimen:D "#1 = \l__str_internal_int sp \scan_stop:
    \tex_skip:D \l__str_internal_int = "#1 sp \scan_stop:
    \tex_toks:D \l__str_internal_int \exp_after:wN { \__int_value:w "#2 }
    \tex_advance:D \l__str_internal_int \c_one
    \__str_decode_eight_bit_load:nn
  }
\cs_new_protected:Npn \__str_decode_eight_bit_load_missing:n #1
  {
    \use_none_delimit_by_q_stop:w #1 \q_stop
    \tex_dimen:D "#1 = \l__str_internal_int sp \scan_stop:
    \tex_skip:D \l__str_internal_int = "#1 sp \scan_stop:
    \tex_toks:D \l__str_internal_int \exp_after:wN
      { \int_use:N \c__str_replacement_char_int }
    \tex_advance:D \l__str_internal_int \c_one
    \__str_decode_eight_bit_load_missing:n
  }
\cs_new:Npn \__str_decode_eight_bit_char:N #1
  {
    #1 \s__tl
    \if_int_compare:w \tex_dimen:D `#1 < \l__str_internal_int
      \if_int_compare:w \tex_skip:D \tex_dimen:D `#1 = `#1 \exp_stop_f:
        \tex_the:D \tex_toks:D \tex_dimen:D
      \fi:
    \fi:
    \__int_value:w `#1 \s__tl
  }
\cs_new_protected:Npn \__str_convert_encode_eight_bit:n #1
  {
    \group_begin:
      \int_zero:N \l__str_internal_int
      \exp_last_unbraced:Nx \__str_encode_eight_bit_load:nn
        { \tl_use:c { c__str_encoding_#1_tl } }
        { \q_stop \__prg_break: } { }
      \__prg_break_point:
      \flag_clear:n { str_error }
      \__str_convert_gmap_internal:N \__str_encode_eight_bit_char:n
      \__str_if_flag_error:nnx { str_error } { encode-8-bit } {#1}
    \group_end:
  }
\cs_new_protected:Npn \__str_encode_eight_bit_load:nn #1#2
  {
    \use_none_delimit_by_q_stop:w #1 \q_stop
    \tex_dimen:D "#2 = \l__str_internal_int sp \scan_stop:
    \tex_skip:D \l__str_internal_int = "#2 sp \scan_stop:
    \exp_args:NNf \tex_toks:D \l__str_internal_int
      { \__str_output_byte:n { "#1 } }
    \tex_advance:D \l__str_internal_int \c_one
    \__str_encode_eight_bit_load:nn
  }
\cs_new:Npn \__str_encode_eight_bit_char:n #1
  {
    \if_int_compare:w #1 > \c_max_register_int
      \flag_raise:n { str_error }
    \else:
      \if_int_compare:w \tex_dimen:D #1 < \l__str_internal_int
        \if_int_compare:w \tex_skip:D \tex_dimen:D #1 = #1 \exp_stop_f:
          \tex_the:D \tex_toks:D \tex_dimen:D #1 \exp_stop_f:
          \exp_after:wN \exp_after:wN \exp_after:wN \use_none:nn
        \fi:
      \fi:
      \__str_encode_eight_bit_char_aux:n {#1}
    \fi:
  }
\cs_new:Npn \__str_encode_eight_bit_char_aux:n #1
  {
    \if_int_compare:w #1 < \c_two_hundred_fifty_six
      \__str_output_byte:n {#1}
    \else:
      \flag_raise:n { str_error }
    \fi:
  }
\__msg_kernel_new:nnn { str } { unknown-esc }
  { Escaping~scheme~'#1'~(filtered:~'#2')~unknown. }
\__msg_kernel_new:nnn { str } { unknown-enc }
  { Encoding~scheme~'#1'~(filtered:~'#2')~unknown. }
\__msg_kernel_new:nnnn { str } { native-escaping }
  { The~'native'~encoding~scheme~does~not~support~any~escaping. }
  {
    Since~native~strings~do~not~consist~in~bytes,~
    none~of~the~escaping~methods~make~sense.~
    The~specified~escaping,~'#1',~will be ignored.
  }
\__msg_kernel_new:nnn { str } { file-not-found }
  { File~'l3str-#1.def'~not~found. }
\pdftex_if_engine:F
  {
    \__msg_kernel_new:nnnn { str } { non-byte }
      { String~invalid~in~escaping~'#1':~it~may~only~contain~bytes. }
      {
        Some~characters~in~the~string~you~asked~to~convert~are~not~
        8-bit~characters.~Perhaps~the~string~is~a~'native'~Unicode~string?~
        If~it~is,~try~using\\
        \\
        \iow_indent:n
          {
            \iow_char:N\\str_set_convert:Nnnn \\
            \ \ <str~var>~\{~<string>~\}~\{~native~\}~\{~<target~encoding>~\}
          }
      }
  }
\__msg_kernel_new:nnnn { str } { decode-8-bit }
  { Invalid~string~in~encoding~'#1'. }
  {
    LaTeX~came~across~a~byte~which~is~not~defined~to~represent~
    any~character~in~the~encoding~'#1'.
  }
\__msg_kernel_new:nnnn { str } { encode-8-bit }
  { Unicode~string~cannot~be~converted~to~encoding~'#1'. }
  {
    The~encoding~'#1'~only~contains~a~subset~of~all~Unicode~characters.~
    LaTeX~was~asked~to~convert~a~string~to~that~encoding,~but~that~
    string~contains~a~character~that~'#1'~does~not~support.
  }
\cs_new_eq:NN \str_length:N \str_count:N
\cs_new_eq:NN \str_length:n \str_count:n
\cs_new_eq:NN \str_length_ignore_spaces:n \str_count_ignore_spaces:n
%% 
%%
%% End of file `l3str.sty'.
