filter an array in place

[Emmanuel Oga <emmanueloga@...>]

Hello, I'm looking for the best proper way of doing this:

local tab = {"a", "a", "c", "a", "d", "a" }

for index, val in ipairs(tab) do
  if val == "a" then -- could be any other complex condition
    table.remove(tab, index)
  end
end

-- WRONG: tab = { "a", "c", "d" }, should be { "c", "d" }

So removing elements from a container _while you are iterating it_ is
wrong in most languages. I'm looking for the nicest and proper way of
doing it.

Two methods I came up with:

1) popping from the array and pushing to a new one if the condition is met.
2) Iterating first, storing indexes to remove, then removing one by
one (compensating index offset as a result of each removed elements)

http://pastie.org/1458808

Is there any other more elegant way?

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