my $got_Pretend; BEGIN { if( $got_Pretend= eval { require Pretend } ) { Pretend->import( qw( sorter hasher ) ); } else { require WorsePretendWorkAround; WorsePretendWorkAround->import( qw( comparer worse_hasher ) ); } } #[...] if( $got_Pretend ) { @list= sorter { $_[0] <=> $_[1] } hasher %hash; } else { @list= sort \&comparer worse_hasher(\%hash); }