statemachine

local loop, event = nil, {} --pre-declare the loop and event

function unblock( func )
    --create the coroutine
    --start with the function parameters
    --unblock( sleep, 1 ) will work because of this
    --pre-declare filter (starts without one)
    local tEventData, co, filter = {}
    return function( ... ) --return a function you can call as many times as you like
        if not co or coroutine.status( co ) == "dead" then --We need a fresh copy of our function
            co = coroutine.create( func )
            tEventData = {...}
            filter = nil
        end
        tEventData = event or {} --get the current event from the statemachine
        if not filter or tEventData[ 1 ] == filter then --if there isn't a filter or the filter matches
            local tVar = {coroutine.resume( co, unpack( tEventData ) )} --we resume the coroutine
            if tVar[ 1 ] and coroutine.status( co ) ~= "dead" then --if the coroutine didn't error and isn't done
                --we have a filter (or lack thereof)
                filter = tVar[ 2 ]
            elseif tVar[ 1 ] then --if the coroutine didn't error but is done
                --we have a returned value, and the execution has finished
                return unpack( tVar )
            elseif coroutine.status( co ) == "dead" then --if the coroutine is dead, but wasn't ok
                --we have an error
                error( tVar[ 2 ], 0 )
            end
        end
    end
end

function setLoop( func ) --sets the loop function to call
    if type( func ) ~= "function" then --if you sent me a value I didn't want
        error( "Expected function, got " .. type( func ), 2 ) --I'm going to tell you
    end
    loop = func
end

function run() --this is the only blocking call of this API, literally to run the program
    while true do
        if loop() then
            break
        end
        event = {os.pullEventRaw()} --this handles event handling for you
    end
end

function pullEvent() --my own pullEvent thing.
    return unpack( event )
end