Re: [xml-dev] Parameterized entities?

[Roger L Costello <costello@mitre.org>]

Thank you David. It is a shame XML doesn’t support parameterized ENTITY’s.

 

I decided to write a simple preprocessor using the Flex lexical analyzer.  It converts the following “fake” ENTITY references:

 

    &file('ARPT.XML');

    &file('NAV.XML');

    &file('TRM.XML');

 

into these XSLT variable declarations:

 

    <xsl:variable name='ARPT.XML' select="doc('ARPT.XML')"/>

    <xsl:variable name='NAV.XML' select="doc('NAV.XML')"/>

    <xsl:variable name='TRM.XML' select="doc('TRM.XML')"/>

 

For those interested, the Flex lexical analyzer that I created is shown below. Here’s how I run it from a command line:

 

more sample.xsl | preprocess > result.xsl

 

Here is the preprocessor (Flex lexical analyzer). I am sure that a skilled C programmer could write much better C code (the stuff within braces below) to extract the filename. If you are a skilled C programmer and have suggestions for improvement, I would love to hear them!

 

%option noyywrap

%{

#include <string.h>

%}

%%

"&file('"[A-Z]+".XML');"           {

                                                           char replacement[20];

                                                           char *start = strstr(yytext, "'");

                                                           char *end   = strstr(yytext, ".");

                                                           int length = end - start - 1;

                                                           char *marker = start + 1;

                                                           int i;

                                                           for (i=0; i<length; i++)

                                                              replacement[i] = *marker++;

                                                           replacement[i]    = '\0';

                                                           fprintf(stdout, "<xsl:variable name='%s.XML' select=\"doc('%s.XML')\"/>", replacement, replacement);

                               }

%%

int main()

{yylex();}