Hello group!

When writing parallel code, I often allocate a vector for results. I
allocate the complete vector with a single resize. What I'd like to do
is to tell the resize not to initialize the content, since this will
be overwritten anyway. I'd figure something like:

struct no_init {} g_no_int;

struct Dummy
{
 Dummy(int a_=0) : a(a_) {}
 Dummy(const no_init &) {} // Without a v-table, this shouldn't need
to
touch any part of the created object?

 int a;
};

void foo()
{
 std::vector<Dummy> dummies;
 dummies.resize(1000, g_no_int);
 // ...
}

Proposal: add a method to std::vector that allows resize with a
different constructor than default or copy
constructor:

               template <typename T2>
               void resize_construct_using_translation(size_t n, const T2 &t2);

Any thoughts on this?

Best regards,
Henrik Vallgren


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