//: So far you can have global variables by not setting default-space, and
//: local variables by setting default-space. You can isolate variables
//: between those extremes by creating 'surrounding' spaces.
//:
//: (Surrounding spaces are like lexical scopes in other languages.)

:(scenario surrounding_space)
# location 1 in space 1 refers to the space surrounding the default space, here 20.
recipe main [
  10:number <- copy 5:literal  # pretend array
  20:number <- copy 5:literal  # pretend array
  default-space:address:array:location <- copy 10:literal
  0:address:array:location/names:dummy <- copy 20:literal  # later layers will explain the /names: property
  1:number <- copy 32:literal
  1:number/space:1 <- copy 33:literal
]
# chain space
+mem: storing 20 in location 11
# store to default-space
+mem: storing 32 in location 12
# store to chained space
+mem: storing 33 in location 22

//: If you think of a space as a collection of variables with a common
//: lifetime, surrounding allows managing shorter lifetimes inside a longer
//: one.

:(replace{} "long long int space_base(const reagent& x)")
long long int space_base(const reagent& x) {
  return space_base(x, space_index(x), Current_routine->calls.