[yul-phaser] Population: Add select() method

tools/yulPhaser/Population.cpp

@@ -17,6 +17,7 @@
 
 #include <tools/yulPhaser/Population.h>
 
+#include <tools/yulPhaser/Selections.h>
 
 #include <libsolutil/CommonData.h>
 #include <libsolutil/CommonIO.h>
@@ -95,6 +96,15 @@ void Population::run(optional<size_t> _numRounds, ostream& _outputStream)
 	}
 }
 
+Population Population::select(Selection const& _selection) const
+{
+	vector<Individual> selectedIndividuals;
+	for (size_t i: _selection.materialise(m_individuals.size()))
+		selectedIndividuals.emplace_back(m_individuals[i]);
+
+	return Population(m_fitnessMetric, selectedIndividuals);
+}
+
 Population operator+(Population _a, Population _b)
 {
 	// This operator is meant to be used only with populations sharing the same metric (and, to make

tools/yulPhaser/Population.h

@@ -39,6 +39,8 @@ solidity::phaser::Population operator+(solidity::phaser::Population _a, solidity
 namespace solidity::phaser
 {
 
+class Selection;
+
 /**
  * Information describing the state of an individual member of the population during the course
  * of the genetic algorithm.
@@ -102,6 +104,7 @@ public:
 	);
 
 	void run(std::optional<size_t> _numRounds, std::ostream& _outputStream);
+	Population select(Selection const& _selection) const;
 	friend Population (::operator+)(Population _a, Population _b);
 
 	std::shared_ptr<FitnessMetric const> fitnessMetric() const { return m_fitnessMetric; }