If a simple scalar C<$valgrind> is passed as the value to C<'valgrind'>, it will be the only candidate.
C<@search_dirs> will then be ignored.
-If an array refernce C<\@valgrind> is passed, its values will be I<prepended> to the list of the candidates resulting from C<@search_dirs>.
+If an array reference C<\@valgrind> is passed, its values will be I<prepended> to the list of the candidates resulting from C<@search_dirs>.
=item *
my $parser_class = $tvt->parser_class($session);
-Returns the class from which the parser for this tool output will be instanciated.
+Returns the class from which the parser for this tool output will be instantiated.
This method must be implemented when subclassing.