Boost C++ Libraries

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Class template metadata_base

boost::histogram::axis::metadata_base — Meta data holder with space optimization for empty meta data types.

Synopsis

// In header: <boost/histogram/axis/metadata_base.hpp>

template<typename Metadata> 
class metadata_base {
public:
  // construct/copy/destruct
  metadata_base() = default;
  metadata_base(const metadata_base &) = default;
  metadata_base(metadata_base &&) noexcept;
  metadata_base(metadata_type &&) noexcept;
  metadata_base & operator=(const metadata_base &) = default;
  metadata_base & operator=(metadata_base &&) noexcept;

  // public member functions
  metadata_type & metadata() noexcept;
  metadata_type & metadata() const noexcept;
};

Description

Allows write-access to metadata even if const.

Template Parameters

```
typename Metadata
```
Wrapped meta data type.

`metadata_base` public construct/copy/destruct

```
metadata_base() = default;
```

metadata_base(const metadata_base &) = default;

metadata_base(metadata_base && o) noexcept;

metadata_base(metadata_type && o) noexcept;

metadata_base & operator=(const metadata_base &) = default;

metadata_base & operator=(metadata_base && o) noexcept;

`metadata_base` public member functions

```
metadata_type & metadata() noexcept;
```
Returns reference to metadata.
```
metadata_type & metadata() const noexcept;
```
Returns reference to mutable metadata from const axis.