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On 25-Jan-07, at 11:22 AM, Jimmie Houchin wrote:

Okay, I learned that '000' is not a valid name in Lua.
But for whatever reason it is accepted successfully as a table index.
I don't if that is something I can depend on or not.

Yes, you can.

If I don't care about losing the syntactic sugar of t.000 for access,
are there other inherent problems with using digit strings to index tables?

No, there aren't. :)

Any Lua object except nil [see note] can be used as a table key. That includes strings (of any kind, which can include \0), numbers (including numbers like 0.5), tables and functions.

Names are just a feature of the compiler: once the script is compiled, there is no difference between a.john and a["john"]. They compile to the same virtual machine code.

[Note: Technically, there is one other object which cannot be used as a key: the "not a number" (NaN) value which can results from invalid mathematical operations like 0/0. That's because, according to "standard" (IEEE-754) semantics, NaN is not equal to itself.]