derivation args question

[jgart]

Hi,

What do the four arguments represent here:

Derive([("out","/gnu/store/c6mqyc4db5s0p01dkd3cmklh2n9vbskc-ed-1.16","","")],
         ^^^^^         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^        ^^ ^^

What do the two arguments represent here:

[("/gnu/store/041ciykg427wkwjy4yjfb5mfv93fvzvp-make-mesboot-3.82.drv",["out"]),
   ^^^^                                                                ^^^^