std::optional

Detailed Description

Specialized functions to read/write a std::optional from/to HDF5.

The following code writes a std::optional to an HDF5 file, reads the same value and outputs it to stdout:

#include <h5/h5.hpp>
#include <iostream>
#include <optional>
 
int main() {
  // create file in read/write mode
  h5::file file("optional.h5", 'w');
 
  // write optional
  h5::write(file, "myoptional", std::optional<float> { 3.1415f });
 
  // read into optional
  std::optional<float> val;
  h5::read(file, "myoptional", val);
 
  // output optional value
  std::cout << *val << std::endl;
}

Output:

3.1415

Contents of optional.h5:

HDF5 "optional.h5" {
GROUP "/" {
   DATASET "myoptional" {
      DATATYPE  H5T_IEEE_F32LE
      DATASPACE  SCALAR
      DATA {
      (0): 3.1415
      }
   }
}
}

Classes
struct	h5::hdf5_format_impl< std::optional< T > >
	Specialization of h5::hdf5_format_impl for std::optional. More...

Functions
template<typename T >
void	h5::h5_read (group g, std::string name, std::optional< T > &opt)
	Read a std::optional from an HDF5 dataset/subgroup.
template<typename T >
void	h5::h5_write (group g, std::string const &name, std::optional< T > const &opt)
	Write a std::optional to an HDF5 dataset/subgroup (if it is set).

Function Documentation

h5_read()

template<typename T >

void h5::h5_read	(	group	g,
		std::string	name,
		std::optional< T > &	opt )

#include <h5/stl/optional.hpp>

Read a std::optional from an HDF5 dataset/subgroup.

Calls the specialized h5_read function for the value type of the std::optional.

Template Parameters

T	Value type of std::optional.

Parameters

g	h5::group containing the dataset/subgroup.
name	Name of the dataset/subgroup from which the std::optional value is read.
opt	std::optional to read into.

Definition at line 71 of file optional.hpp.

h5_write()

template<typename T >

void h5::h5_write	(	group	g,
		std::string const &	name,
		std::optional< T > const &	opt )

#include <h5/stl/optional.hpp>

Write a std::optional to an HDF5 dataset/subgroup (if it is set).

Calls the specialized h5_write function for the value type of the std::optional.

Template Parameters

T	Value type of std::optional.

Parameters

g	h5::group in which the dataset/subgroup is created.
name	Name of the dataset/subgroup to which the std::optional value is written.
opt	std::optional to be written.

Definition at line 56 of file optional.hpp.