It looks like you set $page to "" and then possibly set it to undef in the following line if there is no query parameter named "page". By the time perl compares $page to 'main', it's getting an undef value.

You probably meant something like: my $page = $query->param("page") // '';

or: my $page = $query->param("page") || '';

In reply to Re: string initialization error by perlancar
in thread string initialization error by *alexandre*

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