std::bind1st is deprecated [2]. The function template std::bind provides a better solution [2].

std::bind1st is a binder to call a binary function with the value bound as first argument. If the second argument needs to be bound, use std::bind2nd instead.

The use of std::bind1st is clearest in division:

If on all elements, an element called x, you want to perform '1.0 / x', use std::bind1st one the 1.0. This is demonstrated in the function Reciprocal, which is shown below in the example
If on all elements, an element called x, you want to perform 'x / 2.0', use std::bind2nd one the 2.0. This is demonstrated in the function Halve

Example: Reciprocal

Reciprocal replaces all elements by their reprocicals, that is replaces all elements called 'x' by '1.0/x'.


#include <algorithm>

#include <numeric>

#include <vector>



//From http://www.richelbilderbeek.nl/CppReciprocal.htm

void Reciprocal(std::vector<double>& v)

{

  std::transform(v.begin(),v.end(),v.begin(),

    std::bind1st(std::divides<double>(),1.0));    

}

Advice

Prefer Lambda expressions over binders [1]

References

Scott Meyers. C++ And Beyond 2012 session: 'Initial thoughts on Effective C++11'. 2012. 'Prefer Lambdas over Binders'

Working Draft, Standard for Programming Language C++. 2014-08-22. N3936. Paragraph D.10. 'The binders binder1st, bind1st and bind2nd are deprecated [Note: the function template bind provides a better solution -end note]'

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(C++) std::bind1st

Example: Reciprocal

Advice

References