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Diffstat (limited to 'src/boost/libs/smart_ptr/example/shared_ptr_example.cpp')
-rw-r--r-- | src/boost/libs/smart_ptr/example/shared_ptr_example.cpp | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/src/boost/libs/smart_ptr/example/shared_ptr_example.cpp b/src/boost/libs/smart_ptr/example/shared_ptr_example.cpp new file mode 100644 index 000000000..c3b1f3b42 --- /dev/null +++ b/src/boost/libs/smart_ptr/example/shared_ptr_example.cpp @@ -0,0 +1,95 @@ +// Boost shared_ptr_example.cpp --------------------------------------------// + +// Copyright Beman Dawes 2001. Distributed under the Boost +// Software License, Version 1.0. (See accompanying file +// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) + + +// See http://www.boost.org/libs/smart_ptr for documentation. + +// Revision History +// 21 May 01 Initial complete version (Beman Dawes) + +// The original code for this example appeared in the shared_ptr documentation. +// Ray Gallimore pointed out that foo_set was missing a Compare template +// argument, so would not work as intended. At that point the code was +// turned into an actual .cpp file so it could be compiled and tested. + +#include <vector> +#include <set> +#include <iostream> +#include <algorithm> +#include <boost/shared_ptr.hpp> + +// The application will produce a series of +// objects of type Foo which later must be +// accessed both by occurrence (std::vector) +// and by ordering relationship (std::set). + +struct Foo +{ + Foo( int _x ) : x(_x) {} + ~Foo() { std::cout << "Destructing a Foo with x=" << x << "\n"; } + int x; + /* ... */ +}; + +typedef boost::shared_ptr<Foo> FooPtr; + +struct FooPtrOps +{ + bool operator()( const FooPtr & a, const FooPtr & b ) + { return a->x > b->x; } + void operator()( const FooPtr & a ) + { std::cout << a->x << "\n"; } +}; + +int main() +{ + std::vector<FooPtr> foo_vector; + std::set<FooPtr,FooPtrOps> foo_set; // NOT multiset! + + FooPtr foo_ptr( new Foo( 2 ) ); + foo_vector.push_back( foo_ptr ); + foo_set.insert( foo_ptr ); + + foo_ptr.reset( new Foo( 1 ) ); + foo_vector.push_back( foo_ptr ); + foo_set.insert( foo_ptr ); + + foo_ptr.reset( new Foo( 3 ) ); + foo_vector.push_back( foo_ptr ); + foo_set.insert( foo_ptr ); + + foo_ptr.reset ( new Foo( 2 ) ); + foo_vector.push_back( foo_ptr ); + foo_set.insert( foo_ptr ); + + std::cout << "foo_vector:\n"; + std::for_each( foo_vector.begin(), foo_vector.end(), FooPtrOps() ); + + std::cout << "\nfoo_set:\n"; + std::for_each( foo_set.begin(), foo_set.end(), FooPtrOps() ); + std::cout << "\n"; + +// Expected output: +// +// foo_vector: +// 2 +// 1 +// 3 +// 2 +// +// foo_set: +// 3 +// 2 +// 1 +// +// Destructing a Foo with x=2 +// Destructing a Foo with x=1 +// Destructing a Foo with x=3 +// Destructing a Foo with x=2 + + return 0; +} + |