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On 20-Mar-05, at 5:25 PM, Eric Tetz wrote:
How can I tell the number of elements in table T? I'm not using it as
a list, so table.getn always returns 0. Do I need to write something
like this?

function numelements (t)
  local n = 0
  for k,v in t do
    n = n + 1
  return n


That seems very kludgey.

Perhaps. But why would you want to know?

The closest I usually come to this question is asking whether a table is empty, or sometimes if it has more than one key/value pair. The following are useful:

function is_empty(t) return next(t) == nil end

function is_multiple(t)
  local first = next(t)
  return next(t, first) ~= nil

and for what its worth

function has_at_least(t, n)
  local k = nil
  for i = 1, n do
    k = next(t, k)
    if k == nil then return false end
  return true