Add hint for sizeof too, see #418

Add similar hints for `sizeof` as in 6644bd4

Also, add diagnostics for attempts to use `co_await` and `co_yield` which aren't supported yet (and almost certainly won't be spelled that way)

Author: hsutter

regression-tests/test-results/version

@@ -1,10 +1,11 @@
 
-cppfront compiler v0.2.1   Build 8520:1228
+cppfront compiler v0.2.1   Build 8520:1316
 Copyright(c) Herb Sutter   All rights reserved
 
 SPDX-License-Identifier: CC-BY-NC-ND-4.0
   No commercial use
   No forks/derivatives
-  (At this time, while this is a personal experiment)
+  Note: This license emphasizes that this is a personal
+        experiment; it will be upgraded if that changes
 
 Absolutely no warranty - try at your own risk

source/build.info

@@ -1 +1 @@
-"8520:1228"
+"8520:1316"

source/parse.h

@@ -4474,6 +4474,14 @@ class parser
                 error( "use 'new<" + curr().to_string(true) + ">', not 'new " + curr().to_string(true) + "'", false);
                 return {};
             }
+            if (*n->identifier == "sizeof") {
+                error( "use 'sizeof(" + curr().to_string(true) + ")', not 'sizeof " + curr().to_string(true) + "'", false);
+                return {};
+            }
+            if (*n->identifier == "co_await" || *n->identifier == "co_yield") {
+                error( "(temporary alpha limitation) coroutines are not yet supported in Cpp2", false);
+                return {};
+            }
         }
 
         return n;