error message when trying to jump to primitive

1 files changed, 15 insertions, 0 deletions

diff --git a/shell/environment.mu b/shell/environment.mu
index 06c667fd..51256d02 100644
--- a/shell/environment.mu
+++ b/shell/environment.mu
@@ -277,6 +277,21 @@ fn edit-environment _self: (addr environment), key: grapheme, data-disk: (addr d
         copy-array-object "no such global", go-modal-error-ah
         return
       }
+      # if global is a primitive, set error and return
+      {
+        var global-data-ah/eax: (addr handle array global) <- get globals, data
+        var global-data/eax: (addr array global) <- lookup *global-data-ah
+        var curr-offset/ebx: (offset global) <- compute-offset global-data, curr-index
+        var curr/ebx: (addr global) <- index global-data, curr-offset
+        var curr-value-ah/eax: (addr handle cell) <- get curr, value
+        var curr-value/eax: (addr cell) <- lookup *curr-value-ah
+        var curr-type/eax: (addr int) <- get curr-value, type
+        compare *curr-type, 4/primitive
+        break-if-!=
+        var go-modal-error-ah/eax: (addr handle array byte) <- get self, go-modal-error
+        copy-array-object "sorry, primitives can't be edited yet", go-modal-error-ah
+        return
+      }
       # otherwise clear modal state
       clear-gap-buffer partial-global-name
       var go-modal-error-ah/eax: (addr handle array byte) <- get self, go-modal-error