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On 21/06/16 05:15 PM, Patrick Donnelly wrote:
On Tue, Jun 21, 2016 at 3:59 PM, Sean Conner <> wrote:
It was thus said that the Great Patrick Donnelly once stated:
On Tue, Jun 21, 2016 at 3:22 PM, Soni L. <> 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*.
   Lua 5.3, section 3.4.7:

         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

   But for this discussion:

function foo(...) print(select('#',...) end
function bar(t)   print(#t)             end

There's an echo in this room. Apparently emphasizing **tables** is
lost on people so let me be crystal clear: table length is only
defined for sequences. __So__, while sequences are not nil-safe, that
does __not__ mean tables are not nil-safe.

Thus, tables are not suitable as proper arrays.

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