Index: third_party/libaddressinput/chromium/cpp/include/libaddressinput/util/internal/move.h |
diff --git a/third_party/libaddressinput/chromium/cpp/include/libaddressinput/util/internal/move.h b/third_party/libaddressinput/chromium/cpp/include/libaddressinput/util/internal/move.h |
deleted file mode 100644 |
index e10ce3d4f6b793f321e7517e186518113e5753b4..0000000000000000000000000000000000000000 |
--- a/third_party/libaddressinput/chromium/cpp/include/libaddressinput/util/internal/move.h |
+++ /dev/null |
@@ -1,218 +0,0 @@ |
-// Copyright 2013 The Chromium Authors. All rights reserved. |
-// Use of this source code is governed by a BSD-style license that can be |
-// found in the LICENSE file. |
- |
-#ifndef I18N_ADDRESSINPUT_UTIL_INTERNAL_MOVE_H_ |
-#define I18N_ADDRESSINPUT_UTIL_INTERNAL_MOVE_H_ |
- |
-// Macro with the boilerplate that makes a type move-only in C++03. |
-// |
-// USAGE |
-// |
-// This macro should be used instead of DISALLOW_COPY_AND_ASSIGN to create |
-// a "move-only" type. Unlike DISALLOW_COPY_AND_ASSIGN, this macro should be |
-// the first line in a class declaration. |
-// |
-// A class using this macro must call .Pass() (or somehow be an r-value already) |
-// before it can be: |
-// |
-// * Passed as a function argument |
-// * Used as the right-hand side of an assignment |
-// * Returned from a function |
-// |
-// Each class will still need to define their own "move constructor" and "move |
-// operator=" to make this useful. Here's an example of the macro, the move |
-// constructor, and the move operator= from the scoped_ptr class: |
-// |
-// template <typename T> |
-// class scoped_ptr { |
-// MOVE_ONLY_TYPE_FOR_CPP_03(scoped_ptr, RValue) |
-// public: |
-// scoped_ptr(RValue& other) : ptr_(other.release()) { } |
-// scoped_ptr& operator=(RValue& other) { |
-// swap(other); |
-// return *this; |
-// } |
-// }; |
-// |
-// Note that the constructor must NOT be marked explicit. |
-// |
-// For consistency, the second parameter to the macro should always be RValue |
-// unless you have a strong reason to do otherwise. It is only exposed as a |
-// macro parameter so that the move constructor and move operator= don't look |
-// like they're using a phantom type. |
-// |
-// |
-// HOW THIS WORKS |
-// |
-// For a thorough explanation of this technique, see: |
-// |
-// http://en.wikibooks.org/wiki/More_C%2B%2B_Idioms/Move_Constructor |
-// |
-// The summary is that we take advantage of 2 properties: |
-// |
-// 1) non-const references will not bind to r-values. |
-// 2) C++ can apply one user-defined conversion when initializing a |
-// variable. |
-// |
-// The first lets us disable the copy constructor and assignment operator |
-// by declaring private version of them with a non-const reference parameter. |
-// |
-// For l-values, direct initialization still fails like in |
-// DISALLOW_COPY_AND_ASSIGN because the copy constructor and assignment |
-// operators are private. |
-// |
-// For r-values, the situation is different. The copy constructor and |
-// assignment operator are not viable due to (1), so we are trying to call |
-// a non-existent constructor and non-existing operator= rather than a private |
-// one. Since we have not committed an error quite yet, we can provide an |
-// alternate conversion sequence and a constructor. We add |
-// |
-// * a private struct named "RValue" |
-// * a user-defined conversion "operator RValue()" |
-// * a "move constructor" and "move operator=" that take the RValue& as |
-// their sole parameter. |
-// |
-// Only r-values will trigger this sequence and execute our "move constructor" |
-// or "move operator=." L-values will match the private copy constructor and |
-// operator= first giving a "private in this context" error. This combination |
-// gives us a move-only type. |
-// |
-// For signaling a destructive transfer of data from an l-value, we provide a |
-// method named Pass() which creates an r-value for the current instance |
-// triggering the move constructor or move operator=. |
-// |
-// Other ways to get r-values is to use the result of an expression like a |
-// function call. |
-// |
-// Here's an example with comments explaining what gets triggered where: |
-// |
-// class Foo { |
-// MOVE_ONLY_TYPE_FOR_CPP_03(Foo, RValue); |
-// |
-// public: |
-// ... API ... |
-// Foo(RValue other); // Move constructor. |
-// Foo& operator=(RValue rhs); // Move operator= |
-// }; |
-// |
-// Foo MakeFoo(); // Function that returns a Foo. |
-// |
-// Foo f; |
-// Foo f_copy(f); // ERROR: Foo(Foo&) is private in this context. |
-// Foo f_assign; |
-// f_assign = f; // ERROR: operator=(Foo&) is private in this context. |
-// |
-// |
-// Foo f(MakeFoo()); // R-value so alternate conversion executed. |
-// Foo f_copy(f.Pass()); // R-value so alternate conversion executed. |
-// f = f_copy.Pass(); // R-value so alternate conversion executed. |
-// |
-// |
-// IMPLEMENTATION SUBTLETIES WITH RValue |
-// |
-// The RValue struct is just a container for a pointer back to the original |
-// object. It should only ever be created as a temporary, and no external |
-// class should ever declare it or use it in a parameter. |
-// |
-// It is tempting to want to use the RValue type in function parameters, but |
-// excluding the limited usage here for the move constructor and move |
-// operator=, doing so would mean that the function could take both r-values |
-// and l-values equially which is unexpected. See COMPARED To Boost.Move for |
-// more details. |
-// |
-// An alternate, and incorrect, implementation of the RValue class used by |
-// Boost.Move makes RValue a fieldless child of the move-only type. RValue& |
-// is then used in place of RValue in the various operators. The RValue& is |
-// "created" by doing *reinterpret_cast<RValue*>(this). This has the appeal |
-// of never creating a temporary RValue struct even with optimizations |
-// disabled. Also, by virtue of inheritance you can treat the RValue |
-// reference as if it were the move-only type itself. Unfortunately, |
-// using the result of this reinterpret_cast<> is actually undefined behavior |
-// due to C++98 5.2.10.7. In certain compilers (e.g., NaCl) the optimizer |
-// will generate non-working code. |
-// |
-// In optimized builds, both implementations generate the same assembly so we |
-// choose the one that adheres to the standard. |
-// |
-// |
-// WHY HAVE typedef void MoveOnlyTypeForCPP03 |
-// |
-// Callback<>/Bind() needs to understand movable-but-not-copyable semantics |
-// to call .Pass() appropriately when it is expected to transfer the value. |
-// The cryptic typedef MoveOnlyTypeForCPP03 is added to make this check |
-// easy and automatic in helper templates for Callback<>/Bind(). |
-// See IsMoveOnlyType template and its usage in base/callback_internal.h |
-// for more details. |
-// |
-// |
-// COMPARED TO C++11 |
-// |
-// In C++11, you would implement this functionality using an r-value reference |
-// and our .Pass() method would be replaced with a call to std::move(). |
-// |
-// This emulation also has a deficiency where it uses up the single |
-// user-defined conversion allowed by C++ during initialization. This can |
-// cause problems in some API edge cases. For instance, in scoped_ptr, it is |
-// impossible to make a function "void Foo(scoped_ptr<Parent> p)" accept a |
-// value of type scoped_ptr<Child> even if you add a constructor to |
-// scoped_ptr<> that would make it look like it should work. C++11 does not |
-// have this deficiency. |
-// |
-// |
-// COMPARED TO Boost.Move |
-// |
-// Our implementation similar to Boost.Move, but we keep the RValue struct |
-// private to the move-only type, and we don't use the reinterpret_cast<> hack. |
-// |
-// In Boost.Move, RValue is the boost::rv<> template. This type can be used |
-// when writing APIs like: |
-// |
-// void MyFunc(boost::rv<Foo>& f) |
-// |
-// that can take advantage of rv<> to avoid extra copies of a type. However you |
-// would still be able to call this version of MyFunc with an l-value: |
-// |
-// Foo f; |
-// MyFunc(f); // Uh oh, we probably just destroyed |f| w/o calling Pass(). |
-// |
-// unless someone is very careful to also declare a parallel override like: |
-// |
-// void MyFunc(const Foo& f) |
-// |
-// that would catch the l-values first. This was declared unsafe in C++11 and |
-// a C++11 compiler will explicitly fail MyFunc(f). Unfortunately, we cannot |
-// ensure this in C++03. |
-// |
-// Since we have no need for writing such APIs yet, our implementation keeps |
-// RValue private and uses a .Pass() method to do the conversion instead of |
-// trying to write a version of "std::move()." Writing an API like std::move() |
-// would require the RValue struct to be public. |
-// |
-// |
-// CAVEATS |
-// |
-// If you include a move-only type as a field inside a class that does not |
-// explicitly declare a copy constructor, the containing class's implicit |
-// copy constructor will change from Containing(const Containing&) to |
-// Containing(Containing&). This can cause some unexpected errors. |
-// |
-// http://llvm.org/bugs/show_bug.cgi?id=11528 |
-// |
-// The workaround is to explicitly declare your copy constructor. |
-// |
-#define MOVE_ONLY_TYPE_FOR_CPP_03(type, rvalue_type) \ |
- private: \ |
- struct rvalue_type { \ |
- explicit rvalue_type(type* object) : object(object) {} \ |
- type* object; \ |
- }; \ |
- type(type&); \ |
- void operator=(type&); \ |
- public: \ |
- operator rvalue_type() { return rvalue_type(this); } \ |
- type Pass() { return type(rvalue_type(this)); } \ |
- typedef void MoveOnlyTypeForCPP03; \ |
- private: |
- |
-#endif // I18N_ADDRESSINPUT_UTIL_INTERNAL_MOVE_H_ |