nda::clef::placeholder< N >

#include <nda/clef/placeholder.hpp>

Detailed Description

template<int N>
struct nda::clef::placeholder< N >

A placeholder is an empty struct, labelled by an int.

It is used in lazy expressions. For example:

#include <nda/nda.hpp>
#include <iostream>
 
int main() {
  nda::clef::placeholder<0> i_;
  nda::clef::placeholder<1> j_;
  auto expr = i_ + j_;
  std::cout << nda::clef::eval(expr, i_ = 1.0, j_ = 2.0) << std::endl;
}

Output:

3

Here expr is a lazy binary nda::clef::expr with the nda::clef::tags::plus tag, which can be evaluated later on with the nda::clef::eval function and by assigning values to the placeholders (see nda::clef::pair).

Template Parameters

N	Integer label (must be < 64).

Definition at line 51 of file placeholder.hpp.

Public Member Functions
template<typename... Args>
auto	operator() (Args &&...args) const
	Function call operator.
template<typename RHS>
pair< N, RHS >	operator= (RHS &&rhs) const
	Assign a value to the placeholder.
template<typename T>
auto	operator[] (T &&t) const
	Subscript operator.

Static Public Attributes
static constexpr int	index = N
	Integer label.

Member Function Documentation

operator()()

template<int N>

template<typename... Args>

auto nda::clef::placeholder< N >::operator() ( Args &&... args ) const

inline

Function call operator.

Template Parameters

Args	Types of the function call arguments.

Parameters

args	Function call arguments.

Returns

An nda::clef::expr object with the nda::clef::tags::function tag containing the placeholder (for the callable) and the given arguments.

Definition at line 78 of file placeholder.hpp.

operator=()

template<int N>

template<typename RHS>

pair< N, RHS > nda::clef::placeholder< N >::operator= ( RHS && rhs ) const

inline

Assign a value to the placeholder.

Template Parameters

RHS	Type of the right-hand side.

Parameters

rhs	Right-hand side of the assignment.

Returns

An nda::clef::pair object, containing the integer label of the placeholder and the value assigned to it.

Definition at line 65 of file placeholder.hpp.

operator[]()

template<int N>

template<typename T>

auto nda::clef::placeholder< N >::operator[] ( T && t ) const

inline

Subscript operator.

Template Parameters

T	Type of the subscript argument.

Parameters

t	Subscript argument.

Returns

An nda::clef::expr object with the nda::clef::tags::subscript tag containing the placeholder (for the object to be accessed) and the given argument.

Definition at line 91 of file placeholder.hpp.

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The documentation for this struct was generated from the following file:

• nda/clef/placeholder.hpp