my %foo;
my %bar = ( 1, 2 );

if( $foo{1} = $bar{1} ){
    warn "assignment is assignment";
}

if( $foo{1} = 'any true value'  ){
    warn "assign any true value, expression is true";
}
warn "foo eq bar ", int  ( $foo{1} eq $bar{1} );
__END__
assignment is assignment at - line 5.
assign any true value, expression is true at - line 9.
foo eq bar 0 at - line 11.