Eric Niebler <eric@boost-consulting.com> writes:
Maurizio, deep_copy() alone will not work here. The user is creating a lambda expression and assigning it directly to function<>:
function<int(int&,int&)> f(_0 + _1);
function<> knows nothing about proto expressions, and doesn't know to call proto::deep_copy().
Rats! (apologizes to Dan, I didn't intend to mislead) But now I'd appreciate you entering "grade school mode" and do some explaining. My mental model was: - proto::deep_copy traverse the expression top-down replacing references with value. - generators are used to wrap expressions as they are built bottom-up So, assuming that the expression is properly wrapped in lambda_expr<> why the result of calling proto::expr on the whole expression would be different from using the generator? And why this would tell function<> more about proto expressions? What am I missing? Thanks, Maurizio