util.array: New array library

1 files changed, 45 insertions, 0 deletions

diff --git a/util/array.lua b/util/array.lua
new file mode 100644
index 00000000..5b535fc1
--- /dev/null
+++ b/util/array.lua
@@ -0,0 +1,45 @@
+local array_methods = {};
+local array_mt = { __index = array_methods, __tostring = function (array) return array:concat(", "); end };
+
+local function array(t)
+	return setmetatable(t or {}, array_mt);
+end
+
+function array_methods:map(func, t2)
+	local t2 = t2 or array{};
+	for k,v in ipairs(self) do
+		t2[k] = func(v);
+	end
+	return t2;
+end
+
+function array_methods:filter(func, t2)
+	local t2 = t2 or array{};
+	for k,v in ipairs(self) do
+		if func(v) then
+			t2:push(v);
+		end
+	end
+	return t2;
+end
+
+
+array_methods.push = table.insert;
+array_methods.pop = table.remove;
+array_methods.sort = table.sort;
+array_methods.concat = table.concat;
+array_methods.length = function (t) return #t; end
+
+function array_methods:random()
+	return self[math.random(1,#self)];
+end
+
+function array_methods:shuffle()
+	local len = #self;
+	for i=1,#self do
+		local r = math.random(i,len);
+		self[i], self[r] = self[r], self[i];
+	end
+end
+
+_G.array = array