Generator.h File Reference

#include "Stroika/Foundation/StroikaPreComp.h"
#include "Stroika/Foundation/Traversal/Iterable.h"
#include "Stroika/Foundation/Traversal/Iterator.h"
#include "Generator.inl"

Go to the source code of this file.

Namespaces
namespace	Stroika::Foundation

Functions
template<typename T >
Iterator< T >	Stroika::Foundation::Traversal::CreateGeneratorIterator (const function< optional< T >()> &getNext)
template<typename T >
Iterable< T >	Stroika::Foundation::Traversal::CreateGenerator (const function< optional< T >()> &getNext)
	Create an Iterable<T> from a function that returns optional<T> - treating nullopt as meaning the END of iteration.

Detailed Description

Note

Code-Status: Alpha

TODO:

    "Writeup details on how todo generator � as lambda-from-iteator � like I did for
    revision with queie and lambdas � except we have we construct new object with
    updstream-get-lambda and pass it to downstream one. I think that works. Try draft�."

    I'm now not quite sure what that means. This may have been more for the FunctionApplicaiton module?
    But keep for a little bit to see if it makes sense when I review this code later...

    -- LGP 2013-10-14

Definition in file Generator.h.

Function Documentation

CreateGeneratorIterator()

template<typename T >

Iterator< T > Stroika::Foundation::Traversal::CreateGeneratorIterator

(

const function< optional< T >()> &

getNext

)

Note - if you need to maintain context for the iterator (typically yes) - bind it into the std::function lambda closure (with smart pointers).

Definition at line 14 of file Generator.inl.

CreateGenerator()

template<typename T >

Iterable< T > Stroika::Foundation::Traversal::CreateGenerator

(

const function< optional< T >()> &

getNext

)

Create an Iterable<T> from a function that returns optional<T> - treating nullopt as meaning the END of iteration.

Note - if you need to maintain context for the iterator (typically yes) - bind it into the std::function lambda closure (with smart pointers).

Example Usage

constexpr int kMin = 1;
constexpr int kMax = 10;
auto myContext = make_shared<int> (kMin - 1);
auto getNext = [myContext] () -> optional<int> {
    ++(*myContext);
    if (*myContext > 10)
    {
        return nullopt;
    }
    return *myContext;
};
 
int sum = 0;
for (auto i : CreateGenerator<int> (getNext)) {
    EXPECT_TRUE (1 <= i and i <= 10);
    sum += i;
}
EXPECT_TRUE (sum == (kMax - kMin + 1) * (kMax + kMin) / 2);

Definition at line 55 of file Generator.inl.