Suggestion: table.insert with multiple arguments (was Re: Definition of table.insert)

[GrayFace <sergroj@...>]

Here is a suggestion I've formulated in the "Definition of table.insert" 
thread. Now I've added some more details.

table.insert(table, pos, ...)
Inserts values '...' at position 'pos' in 'table', shifting up other 
elements to open space, if necessary. Returns number of elements 
inserted (i.e. the number of parameters passed as '...'). Alternatively, 
it could be made to return index of the last inserted element. Negative 
or zero 'pos' meant counting from the end of table. E.g. if 'pos' is 0, 
#t+1 is used and arguments are appended to the table.

So, this is backwards incompatible with 2-arguments 'table.insert(t,x)'. 
There'sno special case for 'nil'.
1) The natural use case is when many elements must be inserted. 
Currently this can be done with a custom implementation or by slowly 
inserting elements 1 by 1.
2) Here's another use case I really like:
local t = {}
t.n = table.insert(t, 1, f())
-- packs all return values of f() into a table with length 'n', 
including trailing nil's.

Example:
function f()  return nil, nil  end
-- =>  t = {n = 2}

--
Best regards,
Sergey Rozhenko                 mailto:sergroj@mail.ru