2576 - distinguish allocated addresses from others

This is the one major refinement on the C programming model I'm planning
to introduce in mu. Instead of Rust's menagerie of pointer types and
static checking, I want to introduce just one new type, and use it to
perform ref-counting at runtime.

So far all we're doing is updating new's interface. The actual
ref-counting implementation is next.

One implication: I might sometimes need duplicate implementations for a
recipe with allocated vs vanilla addresses of the same type. So far it
seems I can get away with just always passing in allocated addresses;
the situations when you want to pass an unallocated address to a recipe
should be few and far between.

1 files changed, 5 insertions, 3 deletions

diff --git a/032array.cc b/032array.cc
index f5fe2775..dbc6a4dc 100644
--- a/032array.cc
+++ b/032array.cc
@@ -430,8 +430,10 @@ bool is_mu_string(const reagent& x) {
   return x.type
     && x.type->value == get(Type_ordinal, "address")
     && x.type->right
-    && x.type->right->value == get(Type_ordinal, "array")
+    && x.type->right->value == get(Type_ordinal, "shared")
     && x.type->right->right
-    && x.type->right->right->value == get(Type_ordinal, "character")
-    && x.type->right->right->right == NULL;
+    && x.type->right->right->value == get(Type_ordinal, "array")
+    && x.type->right->right->right
+    && x.type->right->right->right->value == get(Type_ordinal, "character")
+    && x.type->right->right->right->right == NULL;
 }