Arch::FileHighlighter - syntax-highlight file's content using markup

    use Arch::FileHighlighter;
    my $fh = Arch::FileHighlighter->new(
        [ 'internal(pm+c)', 'none(txt), 'enscript', 'internal', ]
    );

    my $html_ref = $fh->highlight($0);
    print $$html_ref;

    print ${$fh->highlight('file.c', '/* some code */')};

This class processes file contents and produces syntax highlighting markup. This may be used together with css that defines exact text colors and faces.

The default is to use the builtin internal processing, that is pretty poor; only very basic file types and syntax constructions are supported. It is suggested to configure and use the external enscript utility. GNU enscript understands quite a rich number of file types and produces a useful syntax highlighting. enscript filter is used by default if /usr/bin/enscript is found.

It is possible to configure different filters (none, internal, enscript) depending on file name extension. In any case the resulting markup is always unified, i.e. all special characters are HTML-encoded using SGML entities, and the markup that looks like <spanclass=syntax_foo>bar</span> is used.

The following methods are available:

new, instance, highlight.

new [filters]

Create a new instance of Arch::FileHighlighter. filters is arrayref of strings of the form filter(ext1+ext2+...)", where filter is one of enscript, internal or none. Special extension :xml is a shortcut for html+htm+sgml+xml+wml+rss+glade. The filters optionally constrained by file extensions are probed sequentially and the first passed one is used. Note that if enscript is configured in the sequence, but is not installed, then its probing may print a warning to stderr. The enscript filter is handled a bit specially, it may take parameters mono (less colors) and asis instead of the file extensions. If enscript returns html without any tags, then the filter is handled as failed, unless asis is given. By default, filters is [ 'internal' ], or [ 'enscript', 'internal' ] depending on presense of '/usr/bin/enscript'.

instance [filters]

Alternative constructor. Return the last created instance of Arch::FileHighlighter or create a new one. The purpose of this alternative constructor is to allow the singleton behaviour as well as certain Aspect Oriented Programming practices.

highlight filename [content]

Process filename using configured filters (as described in the constructor) and produce the file content with embeded <span class="class">...</span> markup. class is one of:

    syntax_keyword
    syntax_builtin
    syntax_comment
    syntax_special
    syntax_funcdef
    syntax_vartype
    syntax_string
    syntax_constant

If content is provided (either string or reference to string), it is used, otherwise the content of filename is loaded.

Awaiting for your reports.

Mikhael Goikhman (migo@homemail.comPerl-GPL/arch-perldevel).

For more information, see enscript, Arch::Util, Syntax::Highlight::Perl.