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% url.sty  ver 3.3    12-Apr-2006   Donald Arseneau   asnd@triumf.ca
% Copyright 1996-2006 Donald Arseneau,  Vancouver, Canada.
% This program can be used, distributed, and modified under the terms
% of the LaTeX Project Public License.
%
% A form of \verb that allows linebreaks at certain characters or
% combinations of characters, accepts reconfiguration, and can usually
% be used in the argument to another command.  It is intended for email
% addresses, hypertext links, directories/paths, etc., which normally
% have no spaces.  The font may be selected using the \urlstyle command,
% and new url-like commands can be defined using \urldef.
%
% Usage:    Conditions:
% \url{ }   If the argument contains any "%" or "^^", or ends with
%           "\", it can't be used in the argument to another command.
%           The argument must not contain unbalanced braces.
% \url|  |  ...where "|" is any character not used in the argument and not
%           "{" or a space.  The same restrictions as above except that the
%           argument may contain unbalanced braces.
% \urldef\xyz\url{ }
% \xyz      a defined-url: "\xyz" can be used anywhere, no matter what
%           characters it contains.
% \DeclareUrlCommand\abc{settings}: makes \abc{ } like \url{ }
%
% See further instructions after "\endinput"
%

% default style assignments
\def\UrlBreaks{\do\.\do\@\do\\\do\/\do\!\do\_\do\|\do\;\do\>\do\]%
 \do\)\do\,\do\?\do\'\do+\do\=\do\#}%
\def\UrlBigBreaks{\do\:\do@url@hyp}%
\def\UrlNoBreaks{\do\(\do\[\do\{\do\<}%
% any ordinary characters that aren't usually:
\def\UrlOrds{\do\*\do\-\do\~\do\'\do\"\do\-}%
\def\UrlSpecials{\do\ {\Url@space}\do\%{\Url@percent}\do\^^M{\Url@space}%
   \Url@force@Tilde}% package option may force faked text-ascii-tilde

\@namedef{Url@OT1encSpecials}{%
  %  *Some* latin-1 or windows characters that ot1 has elsewhere:  OE  oe  ss
  \do\^^8c{\mathchar30 }\do\^^9c{\mathchar27 }\do\^^df{\mathchar25 }%
  \do\~{\lower.45ex\hbox{\m@th$\mathchar126$}}% For tt style
  % lots more to add, but I should later link into inputenc
  \do\^^b5{\mu}%
  \Url@OTnonTT % more for any but typewriter
  }

\def\Url@OTnonTT{\do\<{\langle}\do\>{\mathbin{\rangle}}\do
  \_{\_\penalty\@m}\do\|{\mid}\do\{{\lbrace}\do\}{\mathbin{\rbrace}}\do
  \\{\mathbin{\backslash}}\UrlTildeSpecial}

% *Some* latin-1 or windows characters. Most will pass through safely to T1 enc
% mu  inverted-?  OE  oe
% lots more to add, but I should later link into inputenc
\@namedef{Url@T1encSpecials}{\do\^^b5{\mu}\do\^^bf{\mathchar190 }%
  \do\^^8c{\mathchar215 }\do\^^9c{\mathchar247 }\do\^^df{\mathchar255 }%
  \do\^^ff{\mathchar184 }}

\@namedef{Url@LY1encSpecials}{\do\~{\mathchar158 }}

\def\UrlTildeSpecial{\do\~{\raise.45ex\hbox{\m@th$\scriptstyle\sim$}}}
\let\Url@force@Tilde\relax

\def\url@ttstyle{%
 \@ifundefined{selectfont}{\def\UrlFont{\tt}}{\def\UrlFont{\ttfamily}}}

\def\url@rmstyle{%
 \@ifundefined{selectfont}{\def\UrlFont{\rm}}{\def\UrlFont{\rmfamily}}}

\def\url@sfstyle{%
 \@ifundefined{selectfont}{\def\UrlFont{\sf}}{\def\UrlFont{\sffamily}}}

\def\url@samestyle{\def\UrlFont{}}

\@ifundefined{strip@prefix}{\def\strip@prefix#1>{}}{}
\@ifundefined{verbatim@nolig@list}{\def\verbatim@nolig@list{\do\`}}{}

% \Url sets up the reading the argument verbatim if possible
\def\Url{%
 \Url@movingtest
 \ifmmode\@nomatherr$\fi %$
 \let\do\@makeother \dospecials % verbatim catcodes
 \catcode`{\@ne \catcode`}\tw@ % with exceptions
 \catcode`\ =10 % allow "\url {x}"
 \catcode`\#=6  % always # -> ##, so I can later convert ## -> #
 \@ifnextchar\bgroup{\obeyspaces\obeylines\Url@z}\Url@y}

% \Url@y read arguments delimited like |...|, passing to \Url@z
\def\Url@y#1{\catcode`{11 \catcode`}11\obeyspaces\obeylines
  \def\@tempa##1#1{\Url@z{##1}}\@tempa}

% \Url@z read arguments delimited like {...}, verbatimizes with \meaning,
% performs character translations, then invokes the formatter.
\def\Url@z#1{\toks@{#1}\edef\Url@String{\the\toks@}%
  \edef\Url@String{\expandafter\strip@prefix\meaning\Url@String}%
%\if\urldebug \message{------------------------------------------------------}%
%\message{ \Url@String}\fi
% \meaning introduces spurious spaces in the text, so it would be nice
% to preserve the real spaces before \meaning, but that doesn't work --
% we can only do replacement on streams of non-syntactic characters.
  \Url@ObeySp % may be no-op; otherwise put ordinary (12) space characters
%\if\urldebug \message{ \Url@String}\fi
% we left the catcode of # with its normal value (6) so \meaning
% doubles it to ##.  Now we convert back to single #.  This allows
% \url{#} to appear in the arguments of other commands, where we can't
% make # be an ordinary character.  We make the single # active rather
% than `other' to support hyperref.sty.
  \Url@acthash
%\if\urldebug \message{ \Url@String}\fi
% Also make % active to support hyperref.
  \Url@actpercent
% now do any hyper referencing due to hyperref (or perform a url-def)
  \Url@HyperHook
% Now do the formatting in a group (can also have \Url@HyperHook take
% this as an argument.
  {\Url@FormatString}%
  \endgroup}

\let\Url@ObeySp\@empty
\let\UrlRight\@empty
\let\UrlLeft\@empty
\let\Url@HyperHook\@empty

% This is the normal way to format the strings, using math mode.
\def\Url@FormatString{%
 \UrlFont \Url@MathSetup 
 $\fam\z@ \textfont\z@\font
 \expandafter\UrlLeft\Url@String\UrlRight
 \m@th$%
% \if\urldebug \showlists \fi 
}%

\def\Url@MathSetup{%
 \medmuskip\Urlmuskip \thickmuskip\medmuskip \thinmuskip0mu%
 \relpenalty\UrlBigBreakPenalty \binoppenalty\UrlBreakPenalty
 \expandafter\let\expandafter\UrlEncSpecials\csname Url@\f@encoding encSpecials\endcsname
 % Insert test for unknown encodings here \ifx\UrlEncSpecials\relax
 \ifdim\fontdimen\thr@@\font=\z@ \let\Url@OTnonTT\relax \fi
 \@tempcnta\z@ %  \fam\multiply\@tempcnta\@cclvi
 \let\do\set@mathcode \UrlOrds % ordinary characters that were special
 \advance\@tempcnta 8192 \UrlBreaks % bin
 \advance\@tempcnta 4096 \UrlBigBreaks % rel
 \advance\@tempcnta 4096 \UrlNoBreaks % open
 \let\do\set@mathact \UrlSpecials \UrlEncSpecials % active
 \let\do\set@mathnolig \verbatim@nolig@list % prevent ligatures
}

\def\set@mathcode#1{\count@`#1\advance\count@\@tempcnta
%\message{Set mathcode of \string #1 (\number`#1) = \number`#1 + \number\@tempcnta. }%
\mathcode`#1\count@}
\def\set@mathact#1#2{\mathcode`#1=32768 \begingroup 
    \lccode`\~`#1\lowercase{\endgroup\def~}{#2}}
\def\set@mathnolig#1{\ifnum\mathcode`#1<32768
   \begingroup\lccode`\~`#1\lowercase{\endgroup
     \edef~}{\mathchar\number\mathcode`#1_{\/}}%
   \mathcode`#1=32768 \fi}

\def\Url@movingtest{\begingroup
 \ifx\let\HyPsd@LetCommand % we are already in a pdf string!
  \expandafter\Url@unmove \fi % give the argument and hope for the best
 \let\Url@moving\relax\relax\relax
 \ifx\Url@moving\relax\else \expandafter\Url@unmove \fi
 \endgroup}
\long\def\Url@unmove#1\Url@y{\endgroup \ifx\protect\relax\else\protect\Url\fi}
\edef\Url@moving{\csname Url Error\endcsname}
\expandafter\edef\Url@moving
 {\csname url used in a moving argument.\endcsname}
\expandafter\expandafter\expandafter \let \Url@moving\@undefined

\def\urldef#1#2{\begingroup \setbox\z@\hbox\bgroup
  \def\Url@HyperHook##1\endgroup{\Url@def{#1}{#2}}%
  % Because hyperref breaks \urldef and does not define its own (Grrrr!)...
  \def\url@##1{\egroup\endgroup\DeclareRobustCommand#1{#2{##1}}}%
 #2}
\def\Url@def#1#2{%
   \toks0\expandafter{\Url@String}%
   \protected@edef\Url@String{\Url@String}%
   \toks1\expandafter{\Url@String}%
   \edef\Url@String{\endgroup\egroup\endgroup\def
     \expandafter\noexpand\csname\expandafter\@gobble\string#1 \endcsname
     {\noexpand\Url@eitherdef{\the\toks1}{\noexpand#2{\the\toks0}}}}%
   \Url@String
   \edef#1{\noexpand\protect
      \expandafter\noexpand\csname\expandafter\@gobble\string#1 \endcsname}%
  }
\def\Url@eitherdef{\ifx\let\HyPsd@LetCommand % we are already in a pdf string!
  \expandafter\@firstoftwo \else \expandafter\@secondoftwo \fi}

\def\urlstyle#1{\expandafter\protect\csname url@#1style\endcsname}

\def\DeclareUrlCommand#1#2{\def#1{\leavevmode\begingroup #2\Url}}

% Sample (and default) configuration:
%
\DeclareUrlCommand\url{}
\urlstyle{tt}
%
\newmuskip\Urlmuskip \Urlmuskip=0mu
\mathchardef\UrlBreakPenalty=\binoppenalty
\mathchardef\UrlBigBreakPenalty=\relpenalty
%
% picTeX defines \path, so declare it optionally:
\@ifundefined{path}{\DeclareUrlCommand\path{\urlstyle{tt}}}{}
%
% too many styles define \email like \address, so I will not define it.
% \DeclareUrlCommand\email{\urlstyle{rm}}

% Process LaTeX \package options
%
\let\Url@sppen\@M
\def\Url@space{\penalty\Url@sppen}
\def\do@url@hyp{}% by default, no breaks after hyphens

\@ifundefined{ProvidesPackage}{
}{\ProvidesPackage
 {url}[2006/04/12 \space ver 3.3 \space Verb mode for urls, etc.]
\DeclareOption{hyphens}{\def\do@url@hyp{\do\-}}% allow breaks after hyphens
\DeclareOption{obeyspaces}{\let\Url@ObeySp\relax}% a flag for later
\DeclareOption{spaces}{\def\Url@sppen{\UrlBreakPenalty}}
\DeclareOption{LY1}{}
\DeclareOption{T1}{}
\DeclareOption{allowmove}{\let\Url@moving\@empty}
\DeclareOption{lowtilde}{%
  \def\UrlTildeSpecial{\do\~{\raise.2ex\hbox{\m@th$\scriptstyle\sim$}}}
  \let\Url@force@Tilde\UrlTildeSpecial
}
\ProcessOptions\relax
\ifx\Url@ObeySp\relax % [obeyspaces] was declared
  \begingroup \lccode`+=32 \lowercase
   {\endgroup \def\Url@ObeySp{\Url@Edit\Url@String{ }{+}}}
   \def\Url@space{\penalty\Url@sppen\ }
\fi
}
\ifx\f@encoding\undefined \def\f@encoding{OT1}\fi

\begingroup
% \Url@acthash:    convert `other' (doubled) ## to active #
% \Url@actpercent: convert `other' % to active %
 \lccode`+=`\# \lccode`\~=`\#
  \lowercase {\long\gdef\Url@acthash{\Url@Edit\Url@String{++}{~}%
     \ifnum\mathcode`\#<32768 \def~{\#}\fi}}%
 \lccode`+=`\% \lccode`\~=`\%
  \lowercase {\long\gdef\Url@actpercent{\Url@Edit\Url@String{+}{~}%
    \ifnum\mathcode`\%<32768 \def~{\%}\fi}}%
 \catcode13=12 %
 \gdef\Url@percent{\@ifnextchar^^M{\@gobble}{\mathbin{\mathchar`\%}}}%
\endgroup%

%   Edit macro #1 changing all appearances of pattern #2 to replacement #3.
%   The replacement is recursive, so don't put the search pattern into the
%   replacement text!

{ \catcode`Q=3

\gdef\Url@Edit#1#2#3{%
 \begingroup % \tracingall
 \def\DOE@a{\endgroup\def#1}% Just so I can \expandafter it safely.
 \def\DOE@b##1#2##2Q##3{\@ifblank{##2}% if finished,
   {\DOE@c ##1Q}% then remove \@empty's and redefine macro
   {\DOE@b##1##3##2Q{##3}}% else, re-iterate
 }%  the leading \@empty preserves braces, as does the trailing pattern:
 \expandafter\DOE@b\expandafter\@empty #1\@empty#2Q{#3}}
\gdef\DOE@c#1\@empty Q{\expandafter\DOE@a\expandafter{#1}}
%
%  \@ifblank (LaTeX syntax) --- checks if parameter is blank (Spaces
%     count as blank) use \@ifblank{#1}{true case}{false case} etc
\long\gdef\@ifblank#1{\@Ifbl@nk#1QQ\@secondoftwo\@firstoftwo!}%
\long\gdef\@Ifbl@nk#1#2Q#3#4#5!{#4}

} % restore Q catcode


%\ifx\urldebug\@undefined \def\urldebug{01}\fi

\endinput
%
% url.sty  ver 3.3    12-Apr-2006   Donald Arseneau   asnd@triumf.ca
%
% This package defines "\url", a form of "\verb" that allows linebreaks,
% and can often be used in the argument to another command.  It can be
% configured to print in different formats, and is particularly useful for
% hypertext links, email addresses, directories/paths, etc.  The font may
% be selected using the "\urlstyle" command and pre-defined text can be
% stored with the "\urldef" command. New url-like commands can be defined,
% and a "\path" command is provided this way.
%
% Usage:    Conditions:
% \url{ }   If the argument contains any "%", "#", or "^^", or ends with
%           "\", it can't be used in the argument to another command.
%           The argument must not contain unbalanced braces.
% \url|  |  ...where "|" is any character not used in the argument and not
%           "{" or a space.  The same restrictions as above except that the
%           argument may contain unbalanced braces.
% \xyz      for "\xyz" a defined-url;  this can be used anywhere, no matter
%           what characters it contains.
%
% The "\url" command is fragile, and its argument is likely to be very
% fragile, but a defined-url is robust.
%
% Package Option:  obeyspaces
% Ordinarily, all spaces are ignored in the url-text.  The "[obeyspaces]"
% option allows spaces, but may introduce spurious spaces when a url
% containing "\" characters is given in the argument to another command.
% So if you need to obey spaces you can say "\usepackage[obeyspaces]{url}",
% and if you need both spaces and backslashes, use a `defined-url' for
% anything with "\".
%
% Package Option:  hyphens
% Ordinarily, breaks are not allowed after "-" characters because this
% leads to confusion. (Is the "-" part of the address or just a hyphen?)
% The package option "[hyphens]" allows breaks after explicit hyphen
% characters.  The "\url" command will *never ever* hyphenate words.
%
% Package Option:  spaces
% Likewise, breaks are not usually allowed after spaces under the
% "[obeyspaces]" option, but giving the options "[obeyspaces,spaces]"
% will allow breaks at those spaces. (Note that it seems logical to
% allow the sole option "[spaces]" to let input spaces indicate break
% points, but not to display them in the output. This would be easy to
% implement, but is left out to avoid(?) confusion.)
%
% Package Option:  lowtilde
% Normal treatment of the ~ character is to use the font's "\textasciitilde"
% character, if it has one (or claims to).  Otherwise, the character is
% faked using a mathematic "\sim".  The "[lowtilde]" option causes a
% faked character to be used always (and a bit lower than usual).
%
% Defining a defined-url:
% Take for example the email address "myself%node@gateway.net" which could
% not be given (using "\url" or "\verb") in a caption or parbox due to the
% percent sign.  This address can be predefined with
%    \urldef{\myself}\url{myself%node@gateway.net}   or
%    \urldef{\myself}\url|myself%node@gateway.net|
% and then you may use "\myself" instead of "\url{myself%node@gateway.net}"
% in an argument, and even in a moving argument like a caption because a
% defined-url is robust.
%
% Style:
% You can switch the style of printing using "\urlstyle{tt}", where "tt"
% can be any defined style.  The pre-defined styles are "tt", "rm", "sf",
% and "same" which all allow the same linebreaks but different fonts --
% the first three select a specific font and the "same" style uses the
% current text font.  You can define your own styles with different fonts
% and/or line-breaking by following the explanations below.  The "\url"
% command follows whatever the currently-set style dictates.
%
% Alternate commands:
% It may be desireable to have different things treated differently, each
% in a predefined style; e.g., if you want directory paths to always be
% in typewriter and email addresses to be roman, then you would define new
% url-like commands as follows:
%
%    \DeclareUrlCommand\email{\urlstyle{rm}}
%    \DeclareUrlCommand\directory{\urlstyle{tt}}
%
% In fact, the "\directory" example is exactly the "\path" definition which
% is pre-defined in the package.  If you look above, you will see that "\url"
% is defined with
%    \DeclareUrlCommand\url{}
% I.e., using whatever "\urlstyle" and other settings are already in effect.
%
% You can make a defined-url for these other styles, using the usual
% "\urldef" command as in this example:
%
%    \urldef{\myself}{\email}{myself%node.domain@gateway.net}
%
% which makes "\myself" act like "\email{myself%node.domain@gateway.net}",
% if the "\email" command is defined as above.  The "\myself" command
% would then be robust.
%
% Defining styles:
% Before describing how to customize the printing style, it is best to
% mention something about the unusual implementation of "\url".  Although
% the material is textual in nature, and the font specification required
% is a text-font command, the text is actually typeset in *math* mode.
% This allows the context-sensitive linebreaking, but also accounts for
% the default behavior of ignoring spaces.  Now on to defining styles.
%
% To change the font or the list of characters that allow linebreaks, you
% could redefine the commands "\UrlFont", "\UrlBreaks", "\UrlSpecials" etc.
% directly in the document, but it is better to define a new `url-style'
% (following the example of "\url@ttstyle" and "\url@rmstyle") which defines
% all of "\UrlBigbreaks", "\UrlNoBreaks", "\UrlBreaks", "\UrlSpecials", and
% "\UrlFont".
%
% Changing font:
% The "\UrlFont" command selects the font.  The definition of "\UrlFont"
% done by the pre-defined styles varies to cope with a variety of LaTeX
% font selection schemes, but it could be as simple as "\def\UrlFont{\tt}".
% Depending on the font selected, some characters may need to be defined
% in the "\UrlSpecials" list because many fonts don't contain all the
% standard input characters.
%
% Changing linebreaks:
% The list of characters that allow line-breaks is given by "\UrlBreaks"
% and "\UrlBigBreaks", which have the format "\do\c" for character "c".
% The differences are that `BigBreaks' usually have a lower penalty and have
% different breakpoints when in sequence (as in "http://"): `BigBreaks'
% are treated as mathrels while `Breaks' are mathbins (see The TeXbook,
% p.170). In particular, a series of `BigBreak' characters will break at
% the end and only at the end; a series of `Break' characters will break
% after the first and after every following *pair*; there will be no
% break after a `Break' character if a `BigBreak' follows.  In the case
% of "http://" it doesn't matter whether ":" is a `Break' or `BigBreak' --
% the breaks are the same in either case; but for DECnet nodes with "::"
% it is important to prevent breaks *between* the colons, and that is why
% colons are `BigBreaks'.
%
% It is possible for characters to prevent breaks after the next following
% character (I use this for parentheses).  Specify these in "\UrlNoBreaks".
%
% You can do arbitrarily complex things with characters by making them
% active in math mode (mathcode hex-8000) and specifying the definition(s)
% in "\UrlSpecials".  This is used in the rm and sf styles for OT1 font
% encoding to handle several characters that are not present in those
% computer-modern style fonts.  See the definition of "\Url@do", which
% is used by both "\url@rmstyle" and "\url@sfstyle"; it handles missing
% characters via "\UrlSpecials".  The nominal format for setting each
% special character "c" is: "\do\c{<definition>}", but you can include
% other definitions too.
%
% If all this sounds confusing ... well, it is!  But I hope you won't need
% to redefine breakpoints -- the default assignments seem to work well for
% a wide variety of applications.  If you do need to make changes, you can
% test for breakpoints using regular math mode and the characters "+=(a".
%
% You can allow some spacing around the breakable characters by assigning
%    \Urlmuskip = 0mu plus 1mu
% You can change the penalties used for BigBreaks and Breaks by assigning
%    \mathchardef\UrlBreakPenalty=100 \mathchardef\UrlBigBreakPenalty=100
% The default penalties are "\binoppenalty" and "\relpenalty".  These have
% such odd non-LaTeX syntax because I don't expect people to need to
% change them often.
%
% Yet more flexibility:
% You can also customize the verbatim text by defining "\UrlRight" and/or
% "\UrlLeft", e.g., for ISO formatting of urls surrounded by "<  >", define
%
%    \DeclareUrlCommand\url{\def\UrlLeft{<url:\ }\def\UrlRight{>}%
%        \urlstyle{tt}}
%
% The meanings of "\UrlLeft" and "\UrlRight" are *not* reproduced verbatim.
% This lets you use formatting commands there, but you must be careful not
% to use TeX's special characters ("\^_%~#$&{}" etc.) improperly.
% You can also define "\UrlLeft" to reprocess the verbatim text, but the
% format of the definition is special:
%
%    \def\UrlLeft#1\UrlRight{ ... do things with #1 ... }
%
% Yes, that is "#1" followed by "\UrlRight" then the definition.  For
% example, to put a hyperTeX hypertext link in the DVI file:
%
%    \def\UrlLeft#1\UrlRight{\special{html:<a href="#1">}#1\special{html:</a>}}
%
% Using this technique, url.sty can provide a convenient interface for
% performing various operations on verbatim text.  You don't even need
% to print out the argument!  For greatest efficiency in such obscure
% applications, you can define a null url-style where all the lists like
% "\UrlBreaks" are empty.
%
% Revision History:
% ver 1.1 6-Feb-1996:
% Fix hyphens that wouldn't break and ligatures that weren't suppressed.
% ver 1.2 19-Oct-1996:
% Package option for T1 encoding; Hooks: "\UrlLeft" and "\UrlRight".
% ver 1.3 21-Jul-1997:
% Prohibit spaces as delimiter characters; change ascii tilde in OT1.
% ver 1.4 02-Mar-1999:
% LaTeX license; moving-argument-error
% ver 1.5 28-Mar-1999:
% possibility of spacing around break characters; re-settable penalties
% ver 1.6 20-Jun-2002:
% un-double #, fix obeyed-spaces, ignore trailing %, hook for hyperref
% (\Url@HyperHook), no macros in pre-processed url string (in \Url@String),
% limit catcode change of ~.
% ver 3.0 June 2003/Nov 2003:
% \DeclareUrlCommand; make font encoding automatic (only a few inputenc characters
% are supported yet - needs refactoring); reverse penalties. 
% ver 3.1 Mar 2004:
% Remove spurious spaces in \url@XXstyle commands.
% ver 3.2 June 2005:
% Fix cmsy-symbols in tt bug (from 3.0); LY1 encoding bug; Enable plain
% with miniltx (again); Define the \urldef for hyperref; Lower "sim" tilde
% a little; fix \lowercase error in \UrlSpecials handling.
% ver 3.3 April 2006:
% Fix some encoding bugs and remove 8-bit characters.  lowtilde option
% The End

Test file integrity:  ASCII 32-57, 58-126:  !"#$%&'()*+,-./0123456789
:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~