Function set1

test/doc_uses_allocator.cpp:22–61

//----------------------------------------------------------

static void set1() {

//----------------------------------------------------------
{
// tag::doc_uses_allocator_1[]
// We want to use this resource for all the containers
monotonic_resource mr;

// Declare a vector of JSON values
std::vector< value, boost::container::pmr::polymorphic_allocator< value > > v( &mr );

// The polymorphic allocator will use our resource
assert( v.get_allocator().resource() == &mr );

// Add a string to the vector
v.emplace_back( "boost" );

// The vector propagates the memory resource to the string
assert( v[0].storage().get() == &mr );
// end::doc_uses_allocator_1[]
}
//----------------------------------------------------------
{
// tag::doc_uses_allocator_2[]
// This vector will use the default memory resource
std::vector< value, boost::container::pmr::polymorphic_allocator < value > > v;

// This value will same memory resource as the vector
value jv( v.get_allocator() );

// However, ownership is not transferred,
assert( ! jv.storage().is_shared() );

// and deallocate is never null
assert( ! jv.storage().is_deallocate_trivial() );
// end::doc_uses_allocator_2[]
}
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} // set1

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