Difference in load() with () and other functions

a!localVariables() completely replaces load() and with().

a!localVariables() completely replaces load() and with().

interesting position...I'd be interested in how you'd implement a nested a!forEach() where the inner loop requires a value from each outer loop. Obviously one option would be to write a rule that passed the entire fv!item, from which you'd extract the outer value and all the inner values...but if you wanted to do this without such a helper rule, you could use a with() to define a local!variable that you could set (and re-set) for each outer loop and that is now made available to the inner loop.

Wait, are you saying that couldn't be done with a!localVariables()?  Why?

Because you can't assign a value to a local!variable from within the scope of the a!forEach() - or, if you can, I'm not seeing how that's done. Here's what I've just experimented with. First is what works using a with():

a!localVariables(
  local!myNestedArray: {
    {
      {record: 1, attributes: {"A","B","C"}},
      {record: 2, attributes: {"D","E","F"}}
    },
  },
  a!forEach(
    items: local!myNestedArray,
    expression: with(
      local!currentItem: concat("SJB/", fv!item.record),
      a!forEach(
        items: fv!item.attributes,
        expression: {
          local!currentItem,
          fv!item
        }
      )
    )
  )
)

...and secondly here's what I've tried to do just using local!variables (which I can't get to work):

a!localVariables(
  local!myNestedArray: {
    {
      {record: 1, attributes: {"A","B","C"}},
      {record: 2, attributes: {"D","E","F"}}
    },
  },
  local!currentItem: null,
  a!forEach(
    items: local!myNestedArray,
    expression: {
      local!currentItem: fv!item.record,
      a!forEach(
        items: fv!item.attributes,
        expression: {
          local!currentItem,
          fv!item
        }
      )
    }
  )
)

Arguably (and I might take that position for more a more sophisticated transformation in the inner loop) you'd have a helper rule. And maybe that's best practice, but I'm always (!) suspicious when someone is definitive in their reply! ;-)

Found your problem... you replaced with(), with nothing, instead of a!localVariables()...
Stewart Burchell

should be:

a!localVariables(
  local!myNestedArray: {
    {
      {record: 1, attributes: {"A","B","C"}},
      {record: 2, attributes: {"D","E","F"}}
    },
  },
  local!currentItem: null,
  a!forEach(
    items: local!myNestedArray,
    expression: a!localVariables(
      local!currentItem: fv!item.record,
      a!forEach(
        items: fv!item.attributes,
        expression: {
          local!currentItem,
          fv!item
        }
      )
    )
  )
)