Question

This question is based off some really odd code I recently found in a colleagues work. He claims not to know how it works only he copied it from somewhere else. That’s not good enough for me, I want to understand what’s going on here.

If we have something like:

(test1, test2, test3="3", test4="4")

The result will be that test1 == "3", test2 == "4", test3 == nil and test4 == "4".
I understand why this happens, but if we do something like:

(test1, test2, test3="3", test4="4", test5 = "5", test6 = "6")

now the result is test1 == "3", test2 == "4", test3 == "5", test4 == "4", test5 == "5", test6 == "6".

Why isn’t test5 == nil?

Answer 1

It looks like it’s executing like this:

(test1, test2, test3) = ("3"), (test4 = "4"), (test5 = "5"), (test6 = "6")

# Equivalent:
test1 = "3"
test2 = test4 = "4"
test3 = test5 = "5"
      ; test6 = "6"