Changes when an ent is removed:

When one or more ents are removed by dr dc sk sh commands, is_deleted flag is set.
That makes REF appears in formulas of ents that depend on the deleted ents.
When one or more ents are removed by 'x' command, is_deleted flag is not set.
That preserves references in other ents that depend on the deleted ents, returning zero as
evaluation result.

1 files changed, 3 insertions, 0 deletions

diff --git a/src/gram.y b/src/gram.y
index 6529cb3..20b236d 100644
--- a/src/gram.y
+++ b/src/gram.y
@@ -347,6 +347,7 @@ token K_WHITE
  token K_NUMITER
 */
 %token K_ERR
+%token K_REF
 %token K_LOCALE
 %token K_SET8BIT
 %token K_ASCII
@@ -841,6 +842,8 @@ term:           var                     { $$ = new_var(O_VAR, $1); }
         | '@' K_CHR '(' e ')'           { $$ = new(CHR, $4, ENULL);}
         | '@' K_ERR             { $$ = new(ERR_, ENULL, ENULL); }
         |     K_ERR             { $$ = new(ERR_, ENULL, ENULL); }
+        | '@' K_REF             { $$ = new(REF_, ENULL, ENULL); }
+        |     K_REF             { $$ = new(REF_, ENULL, ENULL); }
 /*
         | '@' K_NUMITER                 { $$ = new(NUMITER, ENULL, ENULL);}
         | '@' K_BLACK           { $$ = new(BLACK, ENULL, ENULL); }