The 1 indexes are only a difference from what you're used to. Lua was made by mathematicians, who of course wanted to address the first element as 1, the second element as 2, etc.

0-indexing makes sense in the context of C where the index operator is syntactic sugar for pointer arithmetic. In higher-level languages like C# and Python and others, it's pretty much just a leftover habit from C devs that we all got used to.

Global by default is a perpetual issue, agreed.

And a lot of the time it makes the syntax more compact than it would be with 0-indexing.

  for i=1,#arr do
    foo(arr[i])
  end

I don't feel that strongly for or against either way of indexing though, they both have their pros and cons.

Perl is usually used with the first element being zero and the same loop would be

    for (0..$#arr) {
        foo(arr[$_])
    }

Whatever you're feeling is not in starting at one.

You are correct that 1-based indexing is the norm among mathematicians, but none of the creators of Lua is a mathematician, AFAIK. You can read about the early history of Lua here:

https://www.lua.org/history.html

> The 1 indexes are only a difference from what you're used to

The left handed scissors are only a difference from what you're used to.

> Lua was made by mathematicians

The default value is nil and using nil as an index on a table returns nil. Yet nil + number is not valid and results in a runtime error.

> it's pretty much just a leftover habit from C devs

It's reflective of the fact that these languages are either intended to work with C APIs or are implemented in C itself. This makes writing FFI and extensions _far_ easier than it would be otherwise.

Lua is the scripting language of [Recoil]. I've been writing some fairly complex game code on it for a few years now, I lost a lot of prejudice over time on 1-indexing.

In fact, at least for this application I've come to enjoy its practicality!

Recoil: https://beyond-all-reason.github.io/RecoilEngine

Lua 5.5 will change the way global variables work: AFAICT you’ll be able to opt out of global-by-default

Too bad the Lua ecosystem is split between 5.4 and 5.1 due to LuaJIT.

I wrote about this in:

https://andregarzia.com/2021/01/lua-a-misunderstood-language...

I like 1 based indexes and the globals don't hurt me on my projects. It is like JS, it has its own bits that are different than other languages, once you learn them you see that it is mostly fine.