util.lua


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--- lam.util

local util = {}

function util.table (x)
	if type(x) == "table" then
		return x
	else
		return { x }
	end
end

function util.pop (tbl)
	return table.remove(tbl, 1)
end

function util.car (tbl)
	return tbl[1]
end

function util.cdr (tbl)
	local t = {}
	for i = 2, #tbl do t[i-1] = tbl[i] end
	return t
end

function util.reduce (tbl, seed, fn)
	if #tbl == 0 then return seed end
	return util.reduce(tbl, fn(seed, util.pop(tbl)), fn)
end

function util.map (fn, tbl)
	local out = {}
	for k, v in pairs(tbl) do
		out[k] = fn(v)
	end
	return out
end

---
return util