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On 21/06/16 04:26 PM, Patrick Donnelly wrote:
On Tue, Jun 21, 2016 at 3:22 PM, Soni L. <fakedme@gmail.com> wrote:But varargs (and thus varargs-based arrays) are nil-safe by default.Show me in the manual where it says **tables** are not nil safe and I'll stop posting to lua-l*. * For today at least.
http://www.lua.org/manual/5.3/manual.html#3.4.7The length operator is denoted by the unary prefix operator #. The length of a string is its number of bytes (that is, the usual meaning of string length when each character is one byte).
A program can modify the behavior of the length operator for any value but strings through the __len metamethod (see §2.4).
Unless a __len metamethod is given, the length of a table t is only defined if the table is a sequence, that is, the set of its positive numeric keys is equal to {1..n} for some non-negative integer n. In that case, n is its length. Note that a table like
{10, 20, nil, 40}
is not a sequence, because it has the key 4 but does not have the key 3.
(So, there is no n such that the set {1..n} is equal to the set of
positive numeric keys of that table.) Note, however, that non-numeric
keys do not interfere with whether a table is a sequence.
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