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Am 03.11.2013 05:50 schröbte Dirk Laurie:

Microlight has 'ifilter'.

--- filter a array using a predicate.
-- If `pred` is absent, then we provide a default which
-- filters out any `false` values.
-- @param t a table
-- @param pred the predicate function
-- @param ... any extra arguments to the predicate
-- @return a array such that `pred(t[i])` is true

This is O(n) and does not destroy the original table.
You can do that yourself by assigning the result of
ifilter to it.

If creating an updated copy instead of removing elements in-place is acceptable, I'd suggest the slightly more general `imodify` function which can replace/remove/insert before/insert after the current element:

      local function helper( t, n, ... )
        local n_v = select( '#', ... )
        for i = 1, n_v do
          t[ n+i ] = select( i, ... )
        return n + n_v

      function imodify( t, cb )
        local new_t, n = {}, 0
        for i = 1, #t do
          n = helper( new_t, n, cb( i, t[ i ] ) )
        return new_t, n