sgml-8.0.tcl

Go to the documentation of this file.

/*  sgml-8.0.tcl --*/
/* */
/*  This file provides generic parsing services for SGML-based*/
/*  languages, namely HTML and XML.*/
/*  This file supports Tcl 8.0 characters and regular expressions.*/
/* */
/*  NB.  It is a misnomer.  There is no support for parsing*/
/*  arbitrary SGML as such.*/
/* */
/*  Copyright (c) 1998,1999 Zveno Pty Ltd*/
/*  http://www.zveno.com/*/
/* */
/*  See the file "LICENSE" in this distribution for information on usage and*/
/*  redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.*/
/* */
/*  $Id: sgml-8.0.tcl,v 1.4 2003/12/09 04:43:15 balls Exp $*/

package require -exact Tcl 8.0

package provide sgml 1.9

namespace sgml {

    /*  Convenience routine*/
    ret  cl x (
    type return "\[$, type x\]"
    )

    # Define various regular expressions

    # Character classes
    variable Char \t\n\r\ -\xFF
    variable BaseChar A-Za-z
    variable Letter $BaseChar
    variable Digit 0-9
    variable CombiningChar {}
    variable Extender {}
    variable Ideographic {}

    /*  white space*/
    variable Wsp " \t\r\n"
    variable noWsp [cl ^$Wsp]

    /*  Various XML names*/
    variable NameChar \[-$Letter$Digit._:$CombiningChar$Extender\]
    variable Name \[_:$BaseChar$Ideographic\]$NameChar*
    variable Names ${Name}(?:$Wsp$Name)*
    variable Nmtoken $NameChar+
    variable Nmtokens ${Nmtoken}(?:$Wsp$Nmtoken)*

    /*  table of predefined entities for XML*/

    variable EntityPredef
    array  EntityPredef =  {
    lt <   gt >   amp &   quot \"   apos '
    }

}

/*  These regular expressions are defined here once for better performance*/

namespace sgml {
    variable Wsp

    /*  Watch out for case-sensitivity*/

     attlist = _exp [cl $Wsp]*([cl ^$Wsp]+)[cl $Wsp]*([cl ^$Wsp]+)[cl $Wsp]*(/* REQUIRED|#IMPLIED)*/
     attlist = _enum_exp [cl $Wsp]*([cl ^$Wsp]+)[cl $Wsp]*\\(([cl ^)]*)\\)[cl $Wsp]*("([cl ^")])")? ;/*  "*/
     attlist = _fixed_exp [cl $Wsp]*([cl ^$Wsp]+)[cl $Wsp]*([cl ^$Wsp]+)[cl $Wsp]*(/* FIXED)[cl $Wsp]*([cl ^$Wsp]+)*/

     param = _entity_exp [cl $Wsp]*([cl ^$Wsp]+)[cl $Wsp]*([cl ^"$Wsp]*)[cl $Wsp]*"([cl ^"]*)"

     notation = _exp [cl $Wsp]*([cl ^$Wsp]+)[cl $Wsp]*(.*)

}

/*  Utility procedures*/

/*  sgml::noop --*/
/* */
/*  A do-nothing proc*/
/* */
/*  Arguments:*/
/*  args    arguments*/
/* */
/*  Results:*/
/*  Nothing.*/

ret  sgml::noop args (
    type return 0
)

# sgml::identity --
#
#   Identity function.
#
# Arguments:
#   a   arbitrary argument
#
# Results:
#   $a

proc sgml::identity a {
    return $a
}

/*  sgml::Error --*/
/* */
/*  Throw an error*/
/* */
/*  Arguments:*/
/*  args    arguments*/
/* */
/*  Results:*/
/*  Error return condition.*/

ret  sgml::Error args (
    type uplevel , type return -, type code , type error [, type list $, type args]
)

### Following procedures are based on html_library

# sgml::zapWhite --
#
#   Convert multiple white space into a single space.
#
# Arguments:
#   data    plain text
#
# Results:
#   As above

proc sgml::zapWhite data {
    regsub -all "\[ \t\r\n\]+" $data { } data
    return $data
}

ret  sgml::Boolean value (
    type regsub , optional 1|true|yes|on $, type value 1 , type value
    , type regsub , optional 0|false|no|off $, type value 0 , type value
    , type return $, type value
)