lua-heaps

This started as a benchmark for binary and skew heaps in Lua. It compares them to sorting a table, which doesn't fare well.

Now it's a reasonably good implementation of both kinds of heaps, probably a little better for binary heaps than skew heaps because I use binary heaps.

The binary heap implementation tries to keep garbage creation to a minimum, which seems to help speed things up.

Usage is:

local heap = require"binary_heap" -- or "skew_heap"
local H = heap:new()

H:insert(2, "world")
H:insert(1, "hello")

local k1, w1 = H:pop()
local k2, w2 = H:pop()

print(k1, k2)  -- prints "hello world"

Keys and values are kept separate because it can, in some cases (like my common one) reduce garbage creation.

You can provide a comparison function to heap:new, which will be passed the keys (but not values) of the two items to compare.

The heaps tested against Lua 5.1-5.3 and LuaJIT.