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55 lines
973 B
Markdown
55 lines
973 B
Markdown
---
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title: "instance_count"
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---
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{{< callout type="info">}}
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Header: `instance_count.h`
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{{< /callout >}}
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Inherit from this class to count instances of a class.
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Before: `20.25.0`
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```cpp
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etl::instance_count<typename T>
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```
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This class is not thread safe.
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From: `20.25.0`
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```cpp
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etl::instance_count<typename T, typename TCounter = uint32_t>
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```
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This class is thread safe if `TCounter` is an *atomic* type.
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## Types
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`type`
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The type being counted.
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`counter_type`
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The type used for the counter.
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## Member functions
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```cpp
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static const counter_type& get_instance_count()
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```
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**Description**
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Returns a const reference to the current count.
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---
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```cpp
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static void reset_instance_count()
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```
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**Description**
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Resets the count to zero.
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## Example
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Instances of `My_Class` will be counted and can be accessed by the inherited member function `get_instance_count()`.
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```cpp
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class My_Class : public etl::instance_count<My_Class, std::atomic_uint8_t>
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{
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};
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```
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