internal/core/adt: improve error message

- Don't use backticks (not used elsewhere)
- fix typo

Change-Id: I825f629c32003287c5d67a0ac63106f0e9e385d5
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/9064
Reviewed-by: CUE cueckoo <cueckoo@gmail.com>
Reviewed-by: Paul Jolly <paul@myitcv.org.uk>
diff --git a/cmd/cue/cmd/testdata/script/vet_embed.txt b/cmd/cue/cmd/testdata/script/vet_embed.txt
index 2ce8030..4ba6c25 100644
--- a/cmd/cue/cmd/testdata/script/vet_embed.txt
+++ b/cmd/cue/cmd/testdata/script/vet_embed.txt
@@ -31,6 +31,6 @@
 e: 2
 
 -- expect-foo --
-field `c` not allowed
+field c not allowed
 -- expect-stream --
-field `d` not allowed
+field d not allowed
diff --git a/cue/testdata/builtins/closed.txtar b/cue/testdata/builtins/closed.txtar
index 501576e..714a6cf 100644
--- a/cue/testdata/builtins/closed.txtar
+++ b/cue/testdata/builtins/closed.txtar
@@ -44,7 +44,7 @@
 
 -- out/eval --
 Errors:
-b: field `x` not allowed:
+b: field x not allowed:
     ./in.cue:1:10
     ./in.cue:5:4
     ./in.cue:5:10
@@ -63,7 +63,7 @@
       b: (int){ int }
     }
     x: (_|_){
-      // [eval] b: field `x` not allowed:
+      // [eval] b: field x not allowed:
       //     ./in.cue:1:10
       //     ./in.cue:5:4
       //     ./in.cue:5:10
diff --git a/cue/testdata/builtins/issue490.txtar b/cue/testdata/builtins/issue490.txtar
index 9d92705..342c939 100644
--- a/cue/testdata/builtins/issue490.txtar
+++ b/cue/testdata/builtins/issue490.txtar
@@ -9,7 +9,7 @@
 }
 -- out/eval --
 Errors:
-B: field `c` not allowed:
+B: field c not allowed:
     ./test.cue:1:10
     ./test.cue:6:4
     ./test.cue:7:2
@@ -26,7 +26,7 @@
     a: (int){ 1 }
     b: (int){ 2 }
     c: (_|_){
-      // [eval] B: field `c` not allowed:
+      // [eval] B: field c not allowed:
       //     ./test.cue:1:10
       //     ./test.cue:6:4
       //     ./test.cue:7:2
diff --git a/cue/testdata/comprehensions/issue293.txtar b/cue/testdata/comprehensions/issue293.txtar
index 30a8166..1072d23 100644
--- a/cue/testdata/comprehensions/issue293.txtar
+++ b/cue/testdata/comprehensions/issue293.txtar
@@ -26,7 +26,7 @@
 t: p: "foo"
 -- out/eval --
 Errors:
-z.x: field `f2` not allowed:
+z.x: field f2 not allowed:
     ./in.cue:2:2
     ./in.cue:5:12
     ./in.cue:11:4
@@ -46,7 +46,7 @@
       // [eval]
       f1: (int){ 99 }
       f2: (_|_){
-        // [eval] z.x: field `f2` not allowed:
+        // [eval] z.x: field f2 not allowed:
         //     ./in.cue:2:2
         //     ./in.cue:5:12
         //     ./in.cue:11:4
diff --git a/cue/testdata/definitions/026_combined_definitions.txtar b/cue/testdata/definitions/026_combined_definitions.txtar
index a5e9bc2..68e3d48 100644
--- a/cue/testdata/definitions/026_combined_definitions.txtar
+++ b/cue/testdata/definitions/026_combined_definitions.txtar
@@ -118,11 +118,11 @@
 }
 -- out/eval --
 Errors:
-#D4.env: field `b` not allowed:
+#D4.env: field b not allowed:
     ./in.cue:26:7
     ./in.cue:27:7
     ./in.cue:30:6
-d1.env: field `c` not allowed:
+d1.env: field c not allowed:
     ./in.cue:3:7
     ./in.cue:4:7
     ./in.cue:9:5
@@ -148,7 +148,7 @@
       a: (string){ "A" }
       b: (string){ "B" }
       c: (_|_){
-        // [eval] d1.env: field `c` not allowed:
+        // [eval] d1.env: field c not allowed:
         //     ./in.cue:3:7
         //     ./in.cue:4:7
         //     ./in.cue:9:5
@@ -176,7 +176,7 @@
       // [eval]
       a: (int){ int }
       b: (_|_){
-        // [eval] #D4.env: field `b` not allowed:
+        // [eval] #D4.env: field b not allowed:
         //     ./in.cue:26:7
         //     ./in.cue:27:7
         //     ./in.cue:30:6
diff --git a/cue/testdata/definitions/032_definitions_with_embedding.txtar b/cue/testdata/definitions/032_definitions_with_embedding.txtar
index 73714a4..7f0703c 100644
--- a/cue/testdata/definitions/032_definitions_with_embedding.txtar
+++ b/cue/testdata/definitions/032_definitions_with_embedding.txtar
@@ -81,7 +81,7 @@
 }
 -- out/eval --
 Errors:
-#e1.a: field `d` not allowed:
+#e1.a: field d not allowed:
     ./in.cue:2:5
     ./in.cue:6:2
     ./in.cue:7:5
@@ -110,7 +110,7 @@
       b: (int){ int }
       c: (int){ int }
       d: (_|_){
-        // [eval] #e1.a: field `d` not allowed:
+        // [eval] #e1.a: field d not allowed:
         //     ./in.cue:2:5
         //     ./in.cue:6:2
         //     ./in.cue:7:5
diff --git "a/cue/testdata/definitions/033_Issue_\043153.txtar" "b/cue/testdata/definitions/033_Issue_\043153.txtar"
index 1524dd4..f527be0 100644
--- "a/cue/testdata/definitions/033_Issue_\043153.txtar"
+++ "b/cue/testdata/definitions/033_Issue_\043153.txtar"
@@ -62,7 +62,7 @@
 }
 -- out/eval --
 Errors:
-listOfCloseds.0: field `b` not allowed:
+listOfCloseds.0: field b not allowed:
     ./in.cue:2:21
     ./in.cue:5:10
     ./in.cue:13:1
@@ -79,7 +79,7 @@
       // [eval]
       a: (int){ |(*(int){ 0 }, (int){ int }) }
       b: (_|_){
-        // [eval] listOfCloseds.0: field `b` not allowed:
+        // [eval] listOfCloseds.0: field b not allowed:
         //     ./in.cue:2:21
         //     ./in.cue:5:10
         //     ./in.cue:13:1
diff --git a/cue/testdata/definitions/037_closing_with_comprehensions.txtar b/cue/testdata/definitions/037_closing_with_comprehensions.txtar
index 95024d2..3be82c8 100644
--- a/cue/testdata/definitions/037_closing_with_comprehensions.txtar
+++ b/cue/testdata/definitions/037_closing_with_comprehensions.txtar
@@ -104,13 +104,13 @@
 }
 -- out/eval --
 Errors:
-#E: field `f3` not allowed:
+#E: field f3 not allowed:
     ./in.cue:1:5
     ./in.cue:27:5
     ./in.cue:27:10
     ./in.cue:28:2
     ./in.cue:29:3
-a: field `f3` not allowed:
+a: field f3 not allowed:
     ./in.cue:1:5
     ./in.cue:3:1
     ./in.cue:4:5
@@ -137,7 +137,7 @@
     f1: (int){ int }
     f2: (int){ int }
     f3: (_|_){
-      // [eval] #E: field `f3` not allowed:
+      // [eval] #E: field f3 not allowed:
       //     ./in.cue:1:5
       //     ./in.cue:27:5
       //     ./in.cue:27:10
@@ -150,7 +150,7 @@
     f1: (int){ int }
     f2: (int){ int }
     f3: (_|_){
-      // [eval] a: field `f3` not allowed:
+      // [eval] a: field f3 not allowed:
       //     ./in.cue:1:5
       //     ./in.cue:3:1
       //     ./in.cue:4:5
diff --git a/cue/testdata/definitions/037_conjunction_of_optional_sets.txtar b/cue/testdata/definitions/037_conjunction_of_optional_sets.txtar
index 5f98c63..b57c59c 100644
--- a/cue/testdata/definitions/037_conjunction_of_optional_sets.txtar
+++ b/cue/testdata/definitions/037_conjunction_of_optional_sets.txtar
@@ -52,14 +52,14 @@
 }
 -- out/eval --
 Errors:
-c: field `aaa` not allowed:
+c: field aaa not allowed:
     ./in.cue:2:2
     ./in.cue:4:5
     ./in.cue:8:5
     ./in.cue:8:10
     ./in.cue:9:5
     ./in.cue:9:11
-d: field `aaa` not allowed:
+d: field aaa not allowed:
     ./in.cue:2:2
     ./in.cue:4:5
     ./in.cue:11:5
@@ -80,7 +80,7 @@
   c: (_|_){
     // [eval]
     aaa: (_|_){
-      // [eval] c: field `aaa` not allowed:
+      // [eval] c: field aaa not allowed:
       //     ./in.cue:2:2
       //     ./in.cue:4:5
       //     ./in.cue:8:5
@@ -94,7 +94,7 @@
   d: (_|_){
     // [eval]
     aaa: (_|_){
-      // [eval] d: field `aaa` not allowed:
+      // [eval] d: field aaa not allowed:
       //     ./in.cue:2:2
       //     ./in.cue:4:5
       //     ./in.cue:11:5
diff --git a/cue/testdata/definitions/038_continue_recursive_closing_for_optionals.txtar b/cue/testdata/definitions/038_continue_recursive_closing_for_optionals.txtar
index 44e2052..eb965c8 100644
--- a/cue/testdata/definitions/038_continue_recursive_closing_for_optionals.txtar
+++ b/cue/testdata/definitions/038_continue_recursive_closing_for_optionals.txtar
@@ -38,7 +38,7 @@
 }
 -- out/eval --
 Errors:
-a.v: field `b` not allowed:
+a.v: field b not allowed:
     ./in.cue:2:12
     ./in.cue:4:4
     ./in.cue:5:6
@@ -53,7 +53,7 @@
     v: (_|_){
       // [eval]
       b: (_|_){
-        // [eval] a.v: field `b` not allowed:
+        // [eval] a.v: field b not allowed:
         //     ./in.cue:2:12
         //     ./in.cue:4:4
         //     ./in.cue:5:6
diff --git a/cue/testdata/definitions/defembed.txtar b/cue/testdata/definitions/defembed.txtar
index 6aee167..9952d67 100644
--- a/cue/testdata/definitions/defembed.txtar
+++ b/cue/testdata/definitions/defembed.txtar
@@ -8,7 +8,7 @@
 #A: b: 1
 -- out/eval --
 Errors:
-a: field `c` not allowed:
+a: field c not allowed:
     ./in.cue:1:4
     ./in.cue:2:5
     ./in.cue:5:4
@@ -21,7 +21,7 @@
     // [eval]
     b: (int){ 1 }
     c: (_|_){
-      // [eval] a: field `c` not allowed:
+      // [eval] a: field c not allowed:
       //     ./in.cue:1:4
       //     ./in.cue:2:5
       //     ./in.cue:5:4
diff --git a/cue/testdata/definitions/embed.txtar b/cue/testdata/definitions/embed.txtar
index 1d045d6..b1fb0be 100644
--- a/cue/testdata/definitions/embed.txtar
+++ b/cue/testdata/definitions/embed.txtar
@@ -76,11 +76,11 @@
 
 -- out/eval --
 Errors:
-reclose1.z: field `d` not allowed:
+reclose1.z: field d not allowed:
     ./in.cue:28:8
     ./in.cue:33:6
     ./in.cue:34:6
-recloseSimple.a: field `b` not allowed:
+recloseSimple.a: field b not allowed:
     ./in.cue:16:9
     ./in.cue:17:6
     ./in.cue:17:7
@@ -113,7 +113,7 @@
     a: (_|_){
       // [eval]
       b: (_|_){
-        // [eval] recloseSimple.a: field `b` not allowed:
+        // [eval] recloseSimple.a: field b not allowed:
         //     ./in.cue:16:9
         //     ./in.cue:17:6
         //     ./in.cue:17:7
@@ -138,7 +138,7 @@
       // [eval]
       c: (int){ int }
       d: (_|_){
-        // [eval] reclose1.z: field `d` not allowed:
+        // [eval] reclose1.z: field d not allowed:
         //     ./in.cue:28:8
         //     ./in.cue:33:6
         //     ./in.cue:34:6
diff --git a/cue/testdata/definitions/hidden.txtar b/cue/testdata/definitions/hidden.txtar
index e39f4b3..cd25867 100644
--- a/cue/testdata/definitions/hidden.txtar
+++ b/cue/testdata/definitions/hidden.txtar
@@ -35,7 +35,7 @@
 
 -- out/eval --
 Errors:
-e._name: field `c` not allowed:
+e._name: field c not allowed:
     ./in.cue:6:10
     ./in.cue:13:13
     ./in.cue:16:10
@@ -68,7 +68,7 @@
       // [eval]
       d: (int){ int }
       c: (_|_){
-        // [eval] e._name: field `c` not allowed:
+        // [eval] e._name: field c not allowed:
         //     ./in.cue:6:10
         //     ./in.cue:13:13
         //     ./in.cue:16:10
diff --git a/cue/testdata/definitions/issue271.txtar b/cue/testdata/definitions/issue271.txtar
index 0d2f296..b88e44d 100644
--- a/cue/testdata/definitions/issue271.txtar
+++ b/cue/testdata/definitions/issue271.txtar
@@ -8,7 +8,7 @@
 }
 -- out/eval --
 Errors:
-x: field `b` not allowed:
+x: field b not allowed:
     ./in.cue:1:5
     ./in.cue:2:11
     ./in.cue:3:4
@@ -24,7 +24,7 @@
     // [eval]
     a: (string){ "hello" }
     b: (_|_){
-      // [eval] x: field `b` not allowed:
+      // [eval] x: field b not allowed:
       //     ./in.cue:1:5
       //     ./in.cue:2:11
       //     ./in.cue:3:4
diff --git a/cue/testdata/definitions/issue320.txtar b/cue/testdata/definitions/issue320.txtar
index be99ac6..f3c144c 100644
--- a/cue/testdata/definitions/issue320.txtar
+++ b/cue/testdata/definitions/issue320.txtar
@@ -12,7 +12,7 @@
 }
 -- out/eval --
 Errors:
-foo: field `y` not allowed:
+foo: field y not allowed:
     ./in.cue:1:7
     ./in.cue:3:2
     ./in.cue:6:8
@@ -31,7 +31,7 @@
     // [eval]
     x: (string){ "hello" }
     y: (_|_){
-      // [eval] foo: field `y` not allowed:
+      // [eval] foo: field y not allowed:
       //     ./in.cue:1:7
       //     ./in.cue:3:2
       //     ./in.cue:6:8
diff --git a/cue/testdata/definitions/issue533.txtar b/cue/testdata/definitions/issue533.txtar
index 1daa2f7..5db9de5 100644
--- a/cue/testdata/definitions/issue533.txtar
+++ b/cue/testdata/definitions/issue533.txtar
@@ -20,11 +20,11 @@
 }
 -- out/eval --
 Errors:
-x1: field `Age` not allowed:
+x1: field Age not allowed:
     ./in.cue:3:5
     ./in.cue:11:5
     ./in.cue:13:2
-x2: field `Age` not allowed:
+x2: field Age not allowed:
     ./in.cue:7:6
     ./in.cue:16:5
     ./in.cue:18:2
@@ -42,7 +42,7 @@
     // [eval]
     Name: (string){ "hello" }
     Age: (_|_){
-      // [eval] x1: field `Age` not allowed:
+      // [eval] x1: field Age not allowed:
       //     ./in.cue:3:5
       //     ./in.cue:11:5
       //     ./in.cue:13:2
@@ -52,7 +52,7 @@
     // [eval]
     Name: (string){ "hello" }
     Age: (_|_){
-      // [eval] x2: field `Age` not allowed:
+      // [eval] x2: field Age not allowed:
       //     ./in.cue:7:6
       //     ./in.cue:16:5
       //     ./in.cue:18:2
diff --git a/cue/testdata/disjunctions/errors.txtar b/cue/testdata/disjunctions/errors.txtar
index 983c466..7fc79a5 100644
--- a/cue/testdata/disjunctions/errors.txtar
+++ b/cue/testdata/disjunctions/errors.txtar
@@ -35,16 +35,16 @@
 -- out/eval --
 Errors:
 issue516.x: 2 errors in empty disjunction:
-issue516.x: field `match` not allowed:
+issue516.x: field match not allowed:
     ./in.cue:20:9
     ./in.cue:22:8
     ./in.cue:23:8
-issue516.x.match.metrics: field `foo` not allowed:
+issue516.x.match.metrics: field foo not allowed:
     ./in.cue:19:25
     ./in.cue:22:8
     ./in.cue:23:24
 issue570.results: 2 errors in empty disjunction:
-issue570.results: field `result` not allowed:
+issue570.results: field result not allowed:
     ./in.cue:2:14
     ./in.cue:3:14
     ./in.cue:7:9
@@ -62,7 +62,7 @@
     // [eval]
     results: (_|_){
       // [eval] issue570.results: 2 errors in empty disjunction:
-      // issue570.results: field `result` not allowed:
+      // issue570.results: field result not allowed:
       //     ./in.cue:2:14
       //     ./in.cue:3:14
       //     ./in.cue:7:9
@@ -73,7 +73,7 @@
       //     ./in.cue:3:22
       //     ./in.cue:12:18
       result: (_|_){
-        // [eval] issue570.results: field `result` not allowed:
+        // [eval] issue570.results: field result not allowed:
         //     ./in.cue:2:14
         //     ./in.cue:3:14
         //     ./in.cue:7:9
@@ -107,16 +107,16 @@
       }) }
     x: (_|_){
       // [eval] issue516.x: 2 errors in empty disjunction:
-      // issue516.x: field `match` not allowed:
+      // issue516.x: field match not allowed:
       //     ./in.cue:20:9
       //     ./in.cue:22:8
       //     ./in.cue:23:8
-      // issue516.x.match.metrics: field `foo` not allowed:
+      // issue516.x.match.metrics: field foo not allowed:
       //     ./in.cue:19:25
       //     ./in.cue:22:8
       //     ./in.cue:23:24
       match: (_|_){
-        // [eval] issue516.x: field `match` not allowed:
+        // [eval] issue516.x: field match not allowed:
         //     ./in.cue:20:9
         //     ./in.cue:22:8
         //     ./in.cue:23:8
diff --git a/cue/testdata/eval/bulk.txtar b/cue/testdata/eval/bulk.txtar
index fd65e50..b533f24 100644
--- a/cue/testdata/eval/bulk.txtar
+++ b/cue/testdata/eval/bulk.txtar
@@ -30,11 +30,11 @@
 
 -- out/eval --
 Errors:
-t1.c: field `z` not allowed:
+t1.c: field z not allowed:
     ./in.cue:15:7
     ./in.cue:19:6
     ./in.cue:19:13
-t2.c: field `z` not allowed:
+t2.c: field z not allowed:
     ./in.cue:23:7
     ./in.cue:27:6
     ./in.cue:27:13
@@ -71,7 +71,7 @@
     c: (_|_){
       // [eval]
       z: (_|_){
-        // [eval] t1.c: field `z` not allowed:
+        // [eval] t1.c: field z not allowed:
         //     ./in.cue:15:7
         //     ./in.cue:19:6
         //     ./in.cue:19:13
@@ -88,7 +88,7 @@
     c: (_|_){
       // [eval]
       z: (_|_){
-        // [eval] t2.c: field `z` not allowed:
+        // [eval] t2.c: field z not allowed:
         //     ./in.cue:23:7
         //     ./in.cue:27:6
         //     ./in.cue:27:13
diff --git a/cue/testdata/eval/closed_disjunction.txtar b/cue/testdata/eval/closed_disjunction.txtar
index b0c2132..0630182 100644
--- a/cue/testdata/eval/closed_disjunction.txtar
+++ b/cue/testdata/eval/closed_disjunction.txtar
@@ -16,13 +16,13 @@
 -- out/eval --
 Errors:
 b: 2 errors in empty disjunction:
-b: field `c` not allowed:
+b: field c not allowed:
     ./in.cue:1:5
     ./in.cue:3:5
     ./in.cue:3:6
     ./in.cue:11:4
     ./in.cue:12:5
-b: field `d` not allowed:
+b: field d not allowed:
     ./in.cue:1:5
     ./in.cue:3:5
     ./in.cue:3:11
@@ -43,20 +43,20 @@
   }
   b: (_|_){
     // [eval] b: 2 errors in empty disjunction:
-    // b: field `c` not allowed:
+    // b: field c not allowed:
     //     ./in.cue:1:5
     //     ./in.cue:3:5
     //     ./in.cue:3:6
     //     ./in.cue:11:4
     //     ./in.cue:12:5
-    // b: field `d` not allowed:
+    // b: field d not allowed:
     //     ./in.cue:1:5
     //     ./in.cue:3:5
     //     ./in.cue:3:11
     //     ./in.cue:11:4
     //     ./in.cue:13:5
     c: (_|_){
-      // [eval] b: field `c` not allowed:
+      // [eval] b: field c not allowed:
       //     ./in.cue:1:5
       //     ./in.cue:3:5
       //     ./in.cue:3:35
@@ -64,7 +64,7 @@
       //     ./in.cue:12:5
     }
     d: (_|_){
-      // [eval] b: field `d` not allowed:
+      // [eval] b: field d not allowed:
       //     ./in.cue:1:5
       //     ./in.cue:3:5
       //     ./in.cue:3:35
diff --git a/cue/testdata/eval/closedness.txtar b/cue/testdata/eval/closedness.txtar
index db75799..70db0af 100644
--- a/cue/testdata/eval/closedness.txtar
+++ b/cue/testdata/eval/closedness.txtar
@@ -18,7 +18,7 @@
 }
 -- out/eval --
 Errors:
-a.q: field `e` not allowed:
+a.q: field e not allowed:
     ./in.cue:1:5
     ./in.cue:6:8
     ./in.cue:7:9
@@ -46,7 +46,7 @@
       c: (int){ 2 }
       d: (int){ int }
       e: (_|_){
-        // [eval] a.q: field `e` not allowed:
+        // [eval] a.q: field e not allowed:
         //     ./in.cue:1:5
         //     ./in.cue:6:8
         //     ./in.cue:7:9
diff --git a/cue/testdata/fulleval/035_optionals_with_label_filters.txtar b/cue/testdata/fulleval/035_optionals_with_label_filters.txtar
index c32a0a8..6b90b91 100644
--- a/cue/testdata/fulleval/035_optionals_with_label_filters.txtar
+++ b/cue/testdata/fulleval/035_optionals_with_label_filters.txtar
@@ -102,13 +102,13 @@
 }
 -- out/eval --
 Errors:
-jobs1: field `foo1` not allowed:
+jobs1: field foo1 not allowed:
     ./in.cue:6:8
     ./in.cue:7:2
     ./in.cue:9:2
     ./in.cue:15:17
     ./in.cue:16:8
-jobs3: field `fooTest1` not allowed:
+jobs3: field fooTest1 not allowed:
     ./in.cue:6:8
     ./in.cue:7:2
     ./in.cue:9:2
@@ -137,7 +137,7 @@
   jobs1: (_|_){
     // [eval]
     foo1: (_|_){
-      // [eval] jobs1: field `foo1` not allowed:
+      // [eval] jobs1: field foo1 not allowed:
       //     ./in.cue:6:8
       //     ./in.cue:7:2
       //     ./in.cue:9:2
@@ -160,7 +160,7 @@
   jobs3: (_|_){
     // [eval]
     fooTest1: (_|_){
-      // [eval] jobs3: field `fooTest1` not allowed:
+      // [eval] jobs3: field fooTest1 not allowed:
       //     ./in.cue:6:8
       //     ./in.cue:7:2
       //     ./in.cue:9:2
diff --git a/cue/testdata/resolve/025_definitions.txtar b/cue/testdata/resolve/025_definitions.txtar
index ad7ec04..52340ce 100644
--- a/cue/testdata/resolve/025_definitions.txtar
+++ b/cue/testdata/resolve/025_definitions.txtar
@@ -119,11 +119,11 @@
 }
 -- out/eval --
 Errors:
-foo: field `feild` not allowed:
+foo: field feild not allowed:
     ./in.cue:1:7
     ./in.cue:12:6
     ./in.cue:13:7
-foo1.recursive: field `feild` not allowed:
+foo1.recursive: field feild not allowed:
     ./in.cue:3:13
     ./in.cue:15:7
     ./in.cue:19:3
@@ -148,7 +148,7 @@
       field: (string){ string }
     }
     feild: (_|_){
-      // [eval] foo: field `feild` not allowed:
+      // [eval] foo: field feild not allowed:
       //     ./in.cue:1:7
       //     ./in.cue:12:6
       //     ./in.cue:13:7
@@ -161,7 +161,7 @@
       // [eval]
       field: (string){ string }
       feild: (_|_){
-        // [eval] foo1.recursive: field `feild` not allowed:
+        // [eval] foo1.recursive: field feild not allowed:
         //     ./in.cue:3:13
         //     ./in.cue:15:7
         //     ./in.cue:19:3
diff --git a/cue/testdata/resolve/029_non-closed_definition_carries_over_closedness_to_enclosed_template.txtar b/cue/testdata/resolve/029_non-closed_definition_carries_over_closedness_to_enclosed_template.txtar
index c184206..8252f79 100644
--- a/cue/testdata/resolve/029_non-closed_definition_carries_over_closedness_to_enclosed_template.txtar
+++ b/cue/testdata/resolve/029_non-closed_definition_carries_over_closedness_to_enclosed_template.txtar
@@ -104,16 +104,16 @@
 }
 -- out/eval --
 Errors:
-a.v: field `b` not allowed:
+a.v: field b not allowed:
     ./in.cue:2:12
     ./in.cue:4:4
     ./in.cue:5:6
 b.w: 1 errors in empty disjunction:
-b.w: field `c` not allowed:
+b.w: field c not allowed:
     ./in.cue:8:12
     ./in.cue:10:4
     ./in.cue:11:6
-c.w.0: field `d` not allowed:
+c.w.0: field d not allowed:
     ./in.cue:14:12
     ./in.cue:14:13
     ./in.cue:16:4
@@ -129,7 +129,7 @@
     v: (_|_){
       // [eval]
       b: (_|_){
-        // [eval] a.v: field `b` not allowed:
+        // [eval] a.v: field b not allowed:
         //     ./in.cue:2:12
         //     ./in.cue:4:4
         //     ./in.cue:5:6
@@ -143,12 +143,12 @@
     // [eval]
     w: (_|_){
       // [eval] b.w: 1 errors in empty disjunction:
-      // b.w: field `c` not allowed:
+      // b.w: field c not allowed:
       //     ./in.cue:8:12
       //     ./in.cue:10:4
       //     ./in.cue:11:6
       c: (_|_){
-        // [eval] b.w: field `c` not allowed:
+        // [eval] b.w: field c not allowed:
         //     ./in.cue:8:12
         //     ./in.cue:8:23
         //     ./in.cue:10:4
@@ -166,7 +166,7 @@
       0: (_|_){
         // [eval]
         d: (_|_){
-          // [eval] c.w.0: field `d` not allowed:
+          // [eval] c.w.0: field d not allowed:
           //     ./in.cue:14:12
           //     ./in.cue:14:13
           //     ./in.cue:16:4
diff --git a/cue/testdata/resolve/030_definitions_with_disjunctions.txtar b/cue/testdata/resolve/030_definitions_with_disjunctions.txtar
index 8dbfbba..5c6fe2b 100644
--- a/cue/testdata/resolve/030_definitions_with_disjunctions.txtar
+++ b/cue/testdata/resolve/030_definitions_with_disjunctions.txtar
@@ -62,7 +62,7 @@
 -- out/eval --
 Errors:
 bar: 1 errors in empty disjunction:
-bar: field `c` not allowed:
+bar: field c not allowed:
     ./in.cue:1:7
     ./in.cue:4:2
     ./in.cue:11:6
@@ -84,14 +84,14 @@
   }
   bar: (_|_){
     // [eval] bar: 1 errors in empty disjunction:
-    // bar: field `c` not allowed:
+    // bar: field c not allowed:
     //     ./in.cue:1:7
     //     ./in.cue:4:2
     //     ./in.cue:11:6
     //     ./in.cue:12:7
     field: (int){ int }
     c: (_|_){
-      // [eval] bar: field `c` not allowed:
+      // [eval] bar: field c not allowed:
       //     ./in.cue:1:7
       //     ./in.cue:4:2
       //     ./in.cue:5:2
diff --git a/cue/testdata/resolve/035_excluded_embedding_from_closing.txtar b/cue/testdata/resolve/035_excluded_embedding_from_closing.txtar
index df94d91..a7352a2 100644
--- a/cue/testdata/resolve/035_excluded_embedding_from_closing.txtar
+++ b/cue/testdata/resolve/035_excluded_embedding_from_closing.txtar
@@ -64,12 +64,12 @@
 }
 -- out/eval --
 Errors:
-V.b: field `extra` not allowed:
+V.b: field extra not allowed:
     ./in.cue:6:10
     ./in.cue:7:5
     ./in.cue:9:4
     ./in.cue:11:5
-V.c: field `e` not allowed:
+V.c: field e not allowed:
     ./in.cue:3:2
     ./in.cue:4:6
     ./in.cue:9:4
@@ -95,7 +95,7 @@
       // [eval]
       d: (int){ int }
       e: (_|_){
-        // [eval] V.c: field `e` not allowed:
+        // [eval] V.c: field e not allowed:
         //     ./in.cue:3:2
         //     ./in.cue:4:6
         //     ./in.cue:9:4
@@ -109,7 +109,7 @@
       // [eval]
       open: (int){ int }
       extra: (_|_){
-        // [eval] V.b: field `extra` not allowed:
+        // [eval] V.b: field extra not allowed:
         //     ./in.cue:6:10
         //     ./in.cue:7:5
         //     ./in.cue:9:4
diff --git a/cue/types.go b/cue/types.go
index b8bec80..caad432 100644
--- a/cue/types.go
+++ b/cue/types.go
@@ -1747,7 +1747,7 @@
 			defer ctx.PopArc(ctx.PushArc(parent))
 			label := a.Label.SelectorString(ctx)
 			parent.Accept(ctx, a.Label)
-			return ctx.NewErrf("field `%s` not allowed", label)
+			return ctx.NewErrf("field %s not allowed", label)
 		}
 	}
 	return nil
diff --git a/cue/types_test.go b/cue/types_test.go
index 3b4c7d1..e2b18e4 100644
--- a/cue/types_test.go
+++ b/cue/types_test.go
@@ -63,7 +63,7 @@
 			res := runSpec.Unify(v)
 			return res
 		},
-		want: "_|_(#runSpec: field `ction` not allowed)",
+		want: "_|_(#runSpec: field ction not allowed)",
 	}, {
 		// Issue #567
 		input: `
@@ -77,7 +77,7 @@
 			res := runSpec.Unify(v)
 			return res
 		},
-		want: "_|_(#runSpec.action: field `Foo` not allowed)",
+		want: "_|_(#runSpec.action: field Foo not allowed)",
 	}, {
 		input: `
 		#runSpec: v: {action: foo: int}
@@ -91,7 +91,7 @@
 			res := w.Unify(v)
 			return res
 		},
-		want: "_|_(#runSpec.v: field `ction` not allowed)",
+		want: "_|_(#runSpec.v: field ction not allowed)",
 	}}
 	for _, tc := range testCases {
 		if tc.skip {
diff --git a/internal/core/adt/closed2.go b/internal/core/adt/closed2.go
index 60496ae..f25c428 100644
--- a/internal/core/adt/closed2.go
+++ b/internal/core/adt/closed2.go
@@ -57,5 +57,5 @@
 	}
 
 	label := f.SelectorString(ctx)
-	return false, ctx.NewErrf("field `%s` not allowed", label)
+	return false, ctx.NewErrf("field %s not allowed", label)
 }
diff --git a/internal/core/subsume/vertex.go b/internal/core/subsume/vertex.go
index 4bc549c..d8ccd10 100644
--- a/internal/core/subsume/vertex.go
+++ b/internal/core/subsume/vertex.go
@@ -157,7 +157,7 @@
 		s.gt = a
 		s.lt = y
 
-		s.errf("field %s not not present in %s",
+		s.errf("field %s not present in %s",
 			f.SelectorString(ctx), ctx.Str(y))
 		return false
 	}