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This builds on the work of @dyoo in https://github.com/google/mdbook-i18n-helpers/pull/69: by adding a special `<!-- mdbook-xgettext: skip -->` comment, we can skip the following code block. I also modified a few code blocks to remove translatable text: variable names are not expected to be translated, so it’s fine to have a line with `println!("foo: {foo}")` in the code block. This PR removes 36 messages from the POT file. The number of lines drop by 633 (3%). Part of #1257.
32 lines
938 B
Markdown
32 lines
938 B
Markdown
# Scope-Based Memory Management
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Constructors and destructors let you hook into the lifetime of an object.
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By wrapping a pointer in an object, you can free memory when the object is
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destroyed. The compiler guarantees that this happens, even if an exception is
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raised.
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This is often called _resource acquisition is initialization_ (RAII) and gives
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you smart pointers.
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## C++ Example
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```c++
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void say_hello(std::unique_ptr<Person> person) {
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std::cout << "Hello " << person->name << std::endl;
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}
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```
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* The `std::unique_ptr` object is allocated on the stack, and points to
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memory allocated on the heap.
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* At the end of `say_hello`, the `std::unique_ptr` destructor will run.
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* The destructor frees the `Person` object it points to.
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Special move constructors are used when passing ownership to a function:
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<!-- mdbook-xgettext: skip -->
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```c++
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std::unique_ptr<Person> person = find_person("Carla");
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say_hello(std::move(person));
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```
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