make my file readable as either Perl or HTML
comments, html, perl
Solution
Read it and weep Mr. @Axeman... I now present to you the empty set:
</dev/fd/0 eval 'exec perl -x -S $0 ${1+"$@"}' #> <!--
#!perl
... some Perl code ...
my $html = << '<!-- END' ; # -->
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
... more HTML ...
</HTML>
<!-- END
... Perl code that processes $html ...
# -->
Problem
In the spirit of the "Perl Preamble" where a script works properly whether executed by a shell script interpreter or the Perl interpreter... I have a Perl script which contains an embedded HTML document (as a "heredoc"), i.e.: ``` #!/usr/bin/perl ... some Perl code ... my $html = <<'END' ; <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> ... more HTML ... </HTML> END ... Perl code that processes $html ... ``` I would like to be able to work on the HTML that's inside the Perl script and check it out using a web browser, and only run the script when the HTML is the way I want. To accomplish this, I need the file to be openable both as an HTML file and as a Perl script. I have tried various tricks with Perl comments and HTML comments but can't get it quite perfect. The file as a whole doesn't have to be "strictly legal" HTML (although the embedded document should be)... just displayable in a browser with no (or minimal) Perl garbage visible. EDIT: Solved! See my own answer