Module HashJoin {
      \\ normally we define variables when we put values to names
      \\ so we can remove these two lines
      Def Name$, Nemesis$
      Def Long m, mc, items_size, A

      \\ Lets make a container which use keys with hash function
      Inventory A
      \\ A now is a pointer to an Inventory, with Len(A)=0
      \\ Print Type$(A)="Inventory"

      \\ empty stack. We use current stack to place data
      Flush
      \Input B
      data "Jonah", "Whales"
      data "Jonah", "Spiders"
      data "Alan", "Ghosts"
      data "Alan", "Zombies"
      data "Glory", "Buffy"
      \\ Keys are unique, This is the HASH PHASE
      While not empty {
            Read Name$, Nemesis$
            If Exist(A, Name$) Then {
                  m=Eval(A)  ' get a pointer to array
                  Stack m {Data Nemesis$}
            } Else Append A, Name$:=Stack:=Nemesis$  ' a stack object with one item
      }
      \\ Input A, this is the Long Table
      data 27, "Jonah"
      data 18, "Alan"
      data 28, "Glory"
      data 18, "Popeye"
      data 28, "Alan"

      \\ This is the JOIN PHASE

      items_size=stack.size/2
      \\ using items_size we can append data (using data) to stack
      \\ $(0) is the default handler for columns.
      \\ Letters justify to left, numbers to right.
      \\ Letters can use more columns, and maybe wrap to more lines.

      Print $(0), "Output during join"
      Print "A.Age", "A.Name","B.Character", "B.Nemesis"
      While items_size>0 {
            Read Age, Name$
            If exist(A, Name$) Then {
                  m=Eval(A)   ' extract a pointer, this is for a stack object
                  mc=Each(m)  ' make an iterator
                  While mc {
                        \\ we use $(1) for left justify numbers too
                        \\ normal StackItem$(stackobject) return top only
                        \\ we have to use StackItem$(stackobject, 3) to get 3rd
                        \\ or StackItem(stackobject, 3) if it is numeric.
                        \\ but here mc is iterator, and place the cursor value to it
                       Print $(1), Age, Name$,Name$, StackItem$(mc)
                        \\ so now we place at the end of current stack the same output
                       Data Age, Name$,Name$, StackItem$(mc)
                  }
            }
            items_size--
      }
      \\ split rem line after : to use second way
      rem : goto secondway
      Print $(0), "Output after join"
      Print "A.Age", "A.Name","B.Character", "B.Nemesis"
      While not Empty {
            Print $(1), Number, Letter$, Letter$, Letter$
      }
      Exit
secondway:
      Print $(0), "Output after join using format$()"
      Print Format$("{0:5} {1:10} {2:10} {3:20}","A.Age", "A.Name","B.Character", "B.Nemesis")
      While not Empty {
            Print format$("{0::5} {1:10} {2:10} {3:20}", Number, Letter$, Letter$, Letter$)
      }
}
HashJoin