michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsIStringEnumerator.h"
michael@0: #include "nsStringFwd.h"
michael@0: #include "nsTArrayForwardDeclare.h"
michael@0: 
michael@0: // nsIStringEnumerator/nsIUTF8StringEnumerator implementations
michael@0: //
michael@0: // Currently all implementations support both interfaces. The
michael@0: // constructors below provide the most common interface for the given
michael@0: // type (i.e. nsIStringEnumerator for char16_t* strings, and so
michael@0: // forth) but any resulting enumerators can be queried to the other
michael@0: // type. Internally, the enumerators will hold onto the type that was
michael@0: // passed in and do conversion if GetNext() for the other type of
michael@0: // string is called.
michael@0: 
michael@0: // There are a few different types of enumerators:
michael@0: 
michael@0: //
michael@0: // These enumerators hold a pointer to the array. Be careful
michael@0: // because modifying the array may confuse the iterator, especially if
michael@0: // you insert or remove elements in the middle of the array.
michael@0: //
michael@0: 
michael@0: // The non-adopting enumerator requires that the array sticks around
michael@0: // at least as long as the enumerator does. These are for constant
michael@0: // string arrays that the enumerator does not own, this could be used
michael@0: // in VERY specialized cases such as when the provider KNOWS that the
michael@0: // string enumerator will be consumed immediately, or will at least
michael@0: // outlast the array.
michael@0: // For example:
michael@0: //
michael@0: // nsTArray<nsCString> array;
michael@0: // array.AppendCString("abc");
michael@0: // array.AppendCString("def");
michael@0: // NS_NewStringEnumerator(&enumerator, &array, true);
michael@0: //
michael@0: // // call some internal method which iterates the enumerator
michael@0: // InternalMethod(enumerator);
michael@0: // NS_RELEASE(enumerator);
michael@0: //
michael@0: nsresult
michael@0: NS_NewStringEnumerator(nsIStringEnumerator** aResult,
michael@0:                        const nsTArray<nsString>* aArray,
michael@0:                        nsISupports* aOwner);
michael@0: nsresult
michael@0: NS_NewUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult,
michael@0:                            const nsTArray<nsCString>* aArray);
michael@0: 
michael@0: nsresult
michael@0: NS_NewStringEnumerator(nsIStringEnumerator** aResult,
michael@0:                        const nsTArray<nsString>* aArray);
michael@0: 
michael@0: // Adopting string enumerators assume ownership of the array and will
michael@0: // call |operator delete| on the array when the enumerator is destroyed
michael@0: // this is useful when the provider creates an array solely for the
michael@0: // purpose of creating the enumerator.
michael@0: // For example:
michael@0: //
michael@0: // nsTArray<nsCString>* array = new nsTArray<nsCString>;
michael@0: // array->AppendString("abcd");
michael@0: // NS_NewAdoptingStringEnumerator(&result, array);
michael@0: nsresult
michael@0: NS_NewAdoptingStringEnumerator(nsIStringEnumerator** aResult,
michael@0:                                nsTArray<nsString>* aArray);
michael@0: 
michael@0: nsresult
michael@0: NS_NewAdoptingUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult,
michael@0:                                    nsTArray<nsCString>* aArray);
michael@0: 
michael@0: 
michael@0: // these versions take a refcounted "owner" which will be addreffed
michael@0: // when the enumerator is created, and destroyed when the enumerator
michael@0: // is released. This allows providers to give non-owning pointers to
michael@0: // ns*StringArray member variables without worrying about lifetime
michael@0: // issues
michael@0: // For example:
michael@0: //
michael@0: // nsresult MyClass::Enumerate(nsIUTF8StringEnumerator** aResult) {
michael@0: //     mCategoryList->AppendString("abcd");
michael@0: //     return NS_NewStringEnumerator(aResult, mCategoryList, this);
michael@0: // }
michael@0: //
michael@0: nsresult
michael@0: NS_NewUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult,
michael@0:                            const nsTArray<nsCString>* aArray,
michael@0:                            nsISupports* aOwner);