my ($operator) = @_;
my %allowed_operators =
map { $_ => 1 }
qw(= != < > <= >= -in -ident -bool -not_bool -or like -like -not_like -between -not_between -not -and -regexp);
qw(= != < > <= >= -in -ident -bool -not_bool -or like -like -not_like -between -not_between -not -and -regexp -not_in);
Koha::Exceptions::REST::Query::InvalidOperator->throw( operator => $operator )
unless exists $allowed_operators{$operator};
return;
-