## menu.icn : rewrite of the faulty version on Rosetta Code site 24/4/2021

procedure main()

L := ["fee fie", "huff and puff", "mirror mirror", "tick tock"]
K := ["hidie hi", "hidie ho", "mirror mirror on the Wall", "tick tock tick tok"]
Z := []

 choice := choose_from_menu(L)      # call using menu L
 write("Returned value =", choice)
 choice := choose_from_menu(K)      # call using menu K
 write("Returned value =", choice)
 choice := choose_from_menu(Z)      # call using empty list
 write("Returned value =", choice)


end ## of main
# --------- subroutines below ---------------------------------

procedure choose_from_menu(X)

 displaymenu(X)
repeat {
   writes("Choose a number from the menu above: ")
   a := read()
   if a == "" then return(a)   ## no selection

  write("You selected ",a)
  if numeric(a) then {
   if integer(a) <= 0 | integer(a) > *X  then displaymenu(X) else
      {                    ## check entered option in range
        write(a, " ==> ",X[a])
      return ( string(a))
	 }
	}
  else displaymenu(X)				
   }

end ## choose_from_menu(X)

procedure displaymenu(X)
	every i := 1 to *X do
		write(i,") ",X[i])    ## dispay menu options
		
end ## displaymenu(X)