Add X::Routine::Banned and ban "length" and "bytes"

src/core/Any.pm

@@ -3,6 +3,7 @@ my class Pair { ... }
 my class Range { ... }
 my class X::Bind::Slice { ... }
 my class X::Bind::ZenSlice { ... }
+my class X::Routine::Banned { ... }
 
 my class Any { # declared in BOOTSTRAP
     # my class Any is Mu {
@@ -264,6 +265,18 @@ my class Any { # declared in BOOTSTRAP
     method KeySet() { DEPRECATED("'SetHash'"); self.SetHash }
     method KeyBag() { DEPRECATED("'BagHash'"); self.BagHash }
 
+    method length is hidden_from_backtrace {
+        fail X::Routine::Banned.new(
+          banned     => ".length",
+          didyoumean => ".chars, .graphs or .codes",
+        );
+    }
+    method bytes is hidden_from_backtrace {
+        fail X::Routine::Banned.new(
+          banned     => ".bytes",
+          didyoumean => ".encode(\$encoding).bytes",
+        );
+    }
 }
 Metamodel::ClassHOW.exclude_parent(Any);
 
@@ -387,6 +400,21 @@ proto sub item(|) is pure { * }
 multi sub item(*@a) { my $ = @a }
 multi sub item(Mu $a) { $a }
 
+proto sub length(|) { * }
+multi sub length (|) is hidden_from_backtrace {
+    fail X::Routine::Banned.new(
+        banned     => "length()",
+        didyoumean => "chars(), graphs() or codes()",
+    )
+}
+proto sub bytes(|) { * }
+multi sub bytes (|) is hidden_from_backtrace {
+    fail X::Routine::Banned.new(
+        banned     => "bytes()",
+        didyoumean => ".encode(\$encoding).bytes",
+    )
+}
+
 my $default= [];       # so that we can check missing parameters
 sub RWPAIR(\k, \v) {   # internal fast pair creation
     my \p := nqp::create(Pair);

src/core/Exception.pm

@@ -1050,6 +1050,15 @@ my class X::Augment::NoSuchType does X::Comp {
     method message() { "You tried to augment $.package-kind $.package, but it does not exist" }
 }
 
+my class X::Routine::Banned is Exception {
+    has $.banned     = "something";
+    has $.didyoumean = "something else";
+    method message() {
+        qq{"$.banned" is banned in Perl 6.
+Did you mean $.didyoumean instead?}
+    }
+}
+
 my class X::Routine::Unwrap is Exception {
     method message() { "Cannot unwrap routine: invalid wrap handle" }
 }