Make C globals in TXR Lisp properly assignable, so that for instance

assigning *stdout*, it really overwrites the underlying C variable.

* eval.c (lookup_var): Handle new kind of toplevel binding.
If the hash value is a cptr, it points to a val storage location.
(lookup_val_l): New function.
(op_modplace): Get location of variable using lookup_val_l
rather than assuming there is a cons-based binding.
(reg_var): Argument changed to val * pointer.
Register the variable as a cptr referencing the location.
(eval_init): reg_var calls pass address of each global.

* eval.h (lookup_var_l): Declared.

1 files changed, 1 insertions, 0 deletions

diff --git a/eval.h b/eval.h
index 0c2fa80a..90eca613 100644
--- a/eval.h
+++ b/eval.h
@@ -28,6 +28,7 @@ val make_env(val fbindings, val vbindings, val up_env);
 val env_fbind(val env, val sym, val fun);
 val env_vbind(val env, val sym, val obj);
 val lookup_var(val env, val sym);
+val *lookup_var_l(val env, val sym);
 val lookup_fun(val env, val sym);
 val interp_fun(val env, val fun, val args);
 val apply(val fun, val arglist, val ctx_form);