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HTML::Lint is a pure-Perl HTML parser and checker for syntactic legitmacy.
It supports only HTML 4.

The "weblint" program that comes with HTML::Lint lets you lint a webpage
or local files.

For those of you doing automated testing with Test::More and the rest
of the Perl testing framework, Test::HTML::Lint lets you automate HTML
checking.

Andy Lester
andy at petdance.com