result of grp.tag - Printable Version

result of grp.tag - Printable Version

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result of grp.tag - rocfusion - 15.06.2016

Hi,

What is the most efficient way of testing for the table object returned by grp.tag? ie is it better to test for the existence of the table or the length or is there something else?

Code:
if (event.type=='groupwrite') then

  local myvl = grp.tag({'VL0','vl'},'all')

  if(myvl) then --existence

    myvl:write(event.getvalue()) 

  end

  local myls = grp.tag({'VL0','ls'},'all')

  if(#myls>0) then  --length

    if (event.getvalue() > 0) then

      myls:write(true)

    else

      myls:write(false)

    end

  end 

end

Thanks,

Roger

RE: result of grp.tag - admin - 15.06.2016

grp.tag always returns a table if valid tag, tag list or tag table is passed. So the correct way is to check table length (#mytable). Still, you can call write and other methods on an empty table returned by grp.tag, it just won't do anything.

RE: result of grp.tag - rocfusion - 15.06.2016

ok thanks