Yes there is: Table-driven programming.

For example, have several different sub-components that each do all of the input processing and HTML generation for a single page, then build a big lookup table (hash) that stores each sub-component name, then have the appropriate sub-component called using some query string parameter you embed in each form. In this example, I use the "op" parameter to tell us what operation (page) we're going to execute, then go look it up in the table, and if it exists, we execute it:

my %sub_components = (
    default_page     => 'defaultpage.comp'
    full_text_search => 'fulltextsearch.comp',
    filename_search  => 'filenamesearch.comp',
    view_alignment   => 'viewalignment.comp',
    add_folder       => 'addfolder.comp'
    ...
);

if ($op) {
    if (exists $sub_components{$op}) {
        # execute the appropriate sub-component:
        eval { $m->comp($sub_components{$op}, %ARGS) };

        if ($@) {
            # handle die() from the sub-component...
        }
    }
    else {
        # handle a request with "op" set to an invalid operation...
    }
}

...

<%args>
$op => 'default_page'
</%args>
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Notice, you have to pass the query string arguments you received by hand to the sub-component you excute using %ARGS. (You have to do this *even* if the sub-components are all defined in the same file as the top-evel component.) Another option is caller_args(), but that's kind of hack-ish.