A null parameter has been passed for month function

Always make sure to make expressions null-safe. i.e. don't process any value that you know already is null.

For the rest the error given is rather clear.

So how to write that?

a!forEach(
  local!items,
  if(
    a!isnullOrEmpty(index(fv!item, "asDate", null)),
    false,
    contains(
      tointeger(local!month),
      month(index(fv!item, "asDate", null))
    )
  )
)

same error occurred yet

What is in ri!taskProductionList? screenshot?

So "asDate" is a field which is in "taskProductionList".table.

Unknown said:

What is in ri!taskProductionList?

Namely, we need to verify that the "asDate" property of that rule input actually contains Date data.  The month() function (afaik) typecasts its input as date, so for example if OP is trying to call this function on String data, it'll still return the same error message as seen here.

moulikadas said:

"asDate" is Date types

Yes, but she mentioned it is of type Date only.

Unknown said:

but she mentioned it is of type Date only

yeah, though from the evidence we're seeing here, it'd be nice to confirm this, because it seems as if it might not be.

Unknown said:

but she mentioned it is of type Date only

yeah, though from the evidence we're seeing here, it'd be nice to confirm this, because it seems as if it might not be.