Add two new array helpers

* create a new array from an old one and a mutation
* mutate all the members of an existing array

1 files changed, 21 insertions, 0 deletions

diff --git a/lib/collections.hpp b/lib/collections.hpp
index ad4d947..5f4be68 100644
--- a/lib/collections.hpp
+++ b/lib/collections.hpp
@@ -12,3 +12,24 @@ operator+(const std::array<T, first> & a, const std::array<T, second> & b)
 	std::copy(b.begin(), b.end(), out);
 	return r;
 }
+
+template<typename T, std::size_t N>
+auto
+operator*(const std::array<T, N> & in, auto && f)
+{
+	std::array<decltype(f(in[0])), N> out;
+
+	for (auto outitr = out.begin(); const auto & v : in) {
+		*outitr++ = f(v);
+	}
+	return out;
+}
+
+template<typename T, std::size_t N>
+auto &
+operator*=(std::array<T, N> & in, auto && f)
+{
+	for (const auto & v : in) {
+		f(v);
+	}
+}