std::extreme_value_distribution<RealType>::extreme_value_distribution

From cppreference.com
extreme_value_distribution( ) : extreme_value_distribution( 0.0 ) { }
(1) (since C++11)
explicit extreme_value_distribution( RealType a, RealType b = 1.0 ) ;
(2) (since C++11)
explicit extreme_value_distribution( const param_type& params ) ;
(3) (since C++11)

Constructs a new distribution object.

2) Uses a and b as the distribution parameters.
3) Uses params as the distribution parameters.

Parameters

a - the a distribution parameter (location)
b - the b distribution parameter (scale)
params - the distribution parameter set

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
P0935R0 C++11 default constructor was explicit made implicit