1 files changed, 90 insertions, 0 deletions
diff --git a/cpp/043space b/cpp/043space
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+//: Spaces help isolate functions from each other. You can create them at will,
+//: and all addresses in arguments are implicitly based on the 'default-space'
+//: (unless they have the /raw property)
+
+:(scenarios run)
+:(scenario "set_default_space")
+# if default-space is 10, and if an array of 5 locals lies from location 11 to 15 (inclusive),
+# then location 0 is really location 11, location 1 is really location 12, and so on.
+recipe main [
+  10:integer <- copy 5:literal  # pretend array; in practice we'll use new
+  default-space:address:space <- copy 10:literal
+  1:integer <- copy 23:literal
+]
++mem: storing 23 in location 12
+
+:(scenario "deref_sidesteps_default_space")
+recipe main [
+  # pretend pointer from outside
+  7:integer <- copy 34:literal
+  # pretend array
+  10:integer <- copy 5:literal
+  # actual start of this function
+  default-space:address:space <- copy 10:literal
+  1:address:integer <- copy 7:literal
+  8:integer/raw <- copy 1:address:integer/deref
+]
++mem: storing 34 in location 8
+
+:(before "End call Fields")
+size_t default_space;
+:(replace "call(recipe_number r) :running_recipe(r)")
+call(recipe_number r) :running_recipe(r), pc(0), next_ingredient_to_process(0), default_space(0) {}
+
+:(replace "reagent r = x" following "reagent canonize(reagent x)")
+reagent r = absolutize(x);
+:(code)
+reagent absolutize(reagent x) {
+//?   if (Recipe_number.find("increment-counter") != Recipe_number.end()) //? 1
+//?     cout << "AAA " << "increment-counter/2: " << Recipe[Recipe_number["increment-counter"]].steps[2].products[0].to_string() << '\n'; //? 1
+//?   cout << "absolutize " << x.to_string() << '\n'; //? 3
+//?   cout << is_raw(x) << '\n'; //? 1
+  if (is_raw(x) || is_dummy(x)) return x;
+//?   cout << "not raw: " << x.to_string() << '\n'; //? 1
+  assert(x.initialized);
+  reagent r = x;
+  r.set_value(address(r.value, space_base(r)));
+//?   cout << "after absolutize: " << r.value << '\n'; //? 1
+  r.properties.push_back(pair<string, vector<string> >("raw", vector<string>()));
+  assert(is_raw(r));
+  return r;
+}
+:(before "return result" following "reagent deref(reagent x)")
+result.properties.push_back(pair<string, vector<string> >("raw", vector<string>()));
+
+:(code)
+int space_base(const reagent& x) {
+  return Current_routine->calls.top().default_space;
+}
+
+int address(int offset, int base) {
+  if (base == 0) return offset;  // raw
+//?   cout << base << '\n'; //? 1
+  if (offset >= Memory[base]) {
+    // todo: test
+    raise << "location " << offset << " is out of bounds " << Memory[base] << '\n';
+  }
+  return base+1 + offset;
+}
+
+:(after "void write_memory(reagent x, vector<int> data)")
+  if (x.name == "default-space") {
+    assert(data.size() == 1);
+    Current_routine->calls.top().default_space = data[0];
+//?     cout << "AAA " << Current_routine->calls.top().default_space << '\n'; //? 1
+    return;
+  }
+
+:(scenario "get_default_space")
+recipe main [
+  default-space:address:space <- copy 10:literal
+  1:integer/raw <- copy default-space:address:space
+]
++mem: storing 10 in location 1
+
+:(after "vector<int> read_memory(reagent x)")
+  if (x.name == "default-space") {
+    vector<int> result;
+    result.push_back(Current_routine->calls.top().default_space);
+    return result;
+  }