hmincrby.lua

-- hmincrby for redis
--
-- Usage:
--   redis-cli EVAL "$(cat hmincrby.lua)" 1 key field1 num1 field2 num2 ... fieldn numn

if 1 ~= table.getn(KEYS) then
    error("Must have exactly 1 key")
end

if 0 ~= table.getn(ARGV) % 2 then
    error("Must have an even number of arguments")
end

local results = {}

for i = 0,  #ARGV / 2 - 1 do
    local f = ARGV[(i * 2) + 1]
    local n = ARGV[(i * 2) + 2]
    -- pcall captures the exception so the error will be in the returned array
    -- of results so the caller should be able to retry just the erroneous
    -- field/num pairs without any double counting
    table.insert(results, redis.pcall('HINCRBY', KEYS[1], f, n))
end

return results