Fix some documentation bugs, closes #1082

Author: hsutter

docs/cpp2/common.md

@@ -67,7 +67,7 @@ All lists use `,` commas between list items, and may be enclosed by
 
 For example:
 
-``` cpp title="Lists, using optional trailing commas just because we can" hl_lines="1 4 6 7"
+``` cpp title="Lists" hl_lines="1 4 6 7"
 print: <T,U> (t: T, u: U) = std::cout << t << u << "\n";
 
 main: () = {

docs/cpp2/expressions.md

@@ -173,13 +173,11 @@ Here are some `as` casts with their Cpp1 equivalents. In this table, uppercase n
 
 ## <a id="inspect"></a> `inspect` — pattern matching
 
-An `inspect expr -> Type` expression allows pattern matching using `is`.
+An `inspect expr -> Type = { /* alternatives */ }` expression allows pattern matching using `is`.
 
 - `expr` is evaluated once.
 
-- Each alternative spelled `is C` is evaluated in order as if called with `expr is C`.
-
-- If an alternative evaluates to `#!cpp true`, then its `#!cpp = alternative;` body is used as the value of the entire `inspect` expression, and the meaning is the same as if the entire `inspect` expression had been written as just `#!cpp :Type = alternative;` — i.e., an unnamed object expression (aka 'temporary object') of type `Type` initialized with `alternative`.
+- Each alternative is spelled `is C = statement;` and are evaluated in order. Each `is C` is evaluated if called with `expr is C`, and if it alternative evaluates to `#!cpp true`, then its `#!cpp = alternative;` body is used as the value of the entire `inspect` expression, and the meaning is the same as if the entire `inspect` expression had been written as just `#!cpp :Type = alternative;` — i.e., an unnamed object expression (aka 'temporary object') of type `Type` initialized with `alternative`.
 
 - A catchall `is _` is required.
 

docs/cpp2/types.md

@@ -81,7 +81,7 @@ For example:
 abstract_base: type
 = {
     //  A pure virtual function: virtual + no body
-    print: (virtual this, msg: std::string);
+    print: (virtual this, msg: std::string) = { /*...*/ }
 
     // ...
 }
@@ -92,7 +92,7 @@ derived: type
     this: abstract_base;
 
     //  Explicit override
-    print: (override this, msg: std::string);
+    print: (override this, msg: std::string) = { /*...*/ }
 
     // ...
 }
@@ -199,7 +199,7 @@ mytype: type
     name:          std::string;
     social_handle: std::string = "(unknown)";
 
-    //  conversion from string
+    //  conversion from string (construction + assignment)
     operator=: (out this, who: std::string) = {
         name = who;
         //  if social_handle is not mentioned, defaults to: