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abrahams_at_[hidden]

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Object Generators
An object generator is a function template whose only purpose is to
construct a new object out of its arguments. Think of it as a kind of
generic constructor. An object generator may be more useful than a plain
constructor when the exact type to be generated is difficult or impossible
to express and the result of the generator can be passed directly to a
function rather than stored in a variable. Most object generators are named
with the prefix "make_", after std::make_pair(const T&, const U&).
Here is an example, using another standard object generator,
std::back_inserter():
// Append the items in [start, finish) to c
template <class Container, class Iterator>
void append_sequence(Container& c, Iterator start, Iterator finish)
{
   std::copy(start, finish, std::back_inserter(c));
}
Without using the object generator the example above would look like: write:
// Append the items in [start, finish) to c
template <class Container, class Iterator>
void append_sequence(Container& c, Iterator start, Iterator finish)
{
   std::copy(start, finish, std::back_insert_iterator<Container>(c));
}
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Unfortunately, this example isn't very compelling. It would be better if the
input to the object generator was the result of calling a function whose
result type was big or impossible to deduce. Can anyone come up with a
plausible example which is more motivating?
Thanks,
Dave