* Simplify @-patterns: only `{attrs}@name' or `name@{attrs}' are now

  allowed.  So `name1@name2', `{attrs1}@{attrs2}' and so on are now no
  longer legal.  This is no big loss because they were not useful
  anyway.

  This also changes the output of builtins.toXML for @-patterns
  slightly.

1 files changed, 1 insertions, 6 deletions

diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 7dddc91a86ab..52292f3f8461 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -846,19 +846,14 @@ static void attrsInPattern(ATermMap & map, Pattern pat)
 {
     ATerm name;
     ATermList formals;
-    Pattern pat1, pat2;
     ATermBool ellipsis;
-    if (matchAttrsPat(pat, formals, ellipsis)) { 
+    if (matchAttrsPat(pat, formals, ellipsis, name)) { 
         for (ATermIterator i(formals); i; ++i) {
             ATerm def;
             if (!matchFormal(*i, name, def)) abort();
             map.set(name, makeAttrRHS(makeBool(def != constNoDefaultValue), makeNoPos()));
         }
     }
-    else if (matchAtPat(pat, pat1, pat2)) {
-        attrsInPattern(map, pat1);
-        attrsInPattern(map, pat2);
-    }
 }