sgml to xml conversion

Question

I have a following sample sgml data from my .sgm file and I want convert this in to xml

xyz
<         


        

Answer 1

Maybe you can use the osx SGML to XML converter. It is part of the OpenSP package (based on SP, originally written by James Clark).

• http://openjade.sourceforge.net/doc/index.htm
• http://www.jclark.com/sp/index.htm

Answer 2

Others have already given some good advice. Here's one way of putting it all together by first converting the input SGML to well-formed XML and then using XSLT to transform that to the exact format you need.

Converting your SGML to well-formed XML

The osx tool from the OpenSP package suggested by mzjn is a good tool for this. Since your SGML markup omits end tags, you need to have a DTD from which the correct nesting of elements can be determined. If you don't have a DTD, you need to create one. For your example input, it could be as simple as this:

<!ELEMENT toplevel o o (viewed)+>

<!ELEMENT viewed - o (#PCDATA,cite)>
<!ELEMENT cite - o (yr,pno)>
<!ELEMENT yr - o (#PCDATA)>
<!ELEMENT pno - o (#PCDATA)>

<!ATTLIST pno cite CDATA #REQUIRED>

You also need to add a proper doctype declaration to the beginning of your SGML file. Assuming you have your DTD in file viewed.dtd.

<!DOCTYPE toplevel SYSTEM "viewed.dtd" >

With this addition, you should now be able use osx to convert the SGML to XML. (It won't be able to convert the processing instructions which start with a / as those are not allowed in XML, and will emit a warning about them.)

osx input.sgm > input.xml

Transforming the resulting XML to your desired format

For the above case, you could use something like the following XSLT stylesheet:

<xsl:stylesheet version="1.0"
                xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output method="xml" indent="yes"/>
  <xsl:template match="VIEWED">
    <index1>
      <num viewed="{normalize-space(text())}"/>
      <heading>
        <xsl:value-of select="normalize-space(text())"/>
      </heading>
      <index-refs>
        <xsl:apply-templates select="CITE"/>
      </index-refs>
    </index1>
  </xsl:template>

  <xsl:template match="CITE">
    <link caseno="{PNO/@CITE}"/>
  </xsl:template>

</xsl:stylesheet>

Answer 3

Why XSLT? I doubt you can map SGML to XML Infoset or XDM...

I think that you should better use the language made for this task: DSSSL (Document Style Semantics and Specification Language)

This is the predecessor of XSLT. The author is James Clark. And this is the his site.

Answer 4

Can the SGML-Reader, originally developed by Chris Lovett help in solving this problem?