[Q] how to anticipate last iteration in for .. in pairs

["V S P" <toreason@...>]

Hello,
what's a way to anticipate the last iteration
in loop over a table

for colnm, coltype in pairs(tb_columns) do


I understand that I can get the table length, and then
increment a counter, but for some reason I thought
the table length thing was not reliable at all the cases...
but cannot find a reference to it

is there a better way?


thank you
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  V S P
  toreason@fastmail.fm

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