Changeset f3be342

Timestamp:

Apr 12, 2017, 9:50:45 AM (8 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

ADT, aaron-thesis, arm-eh, ast-experimental, cleanup-dtors, deferred_resn, demangler, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, new-env, no_list, persistent-indexer, pthread-emulation, qualifiedEnum, resolv-new, with_gc

Children:

eaa2f3a1

Parents:

3720bf8f

Message:

more cleanup for pages 1-8

File:

• doc/generic_types/generic_types.tex (modified) (2 diffs)

doc/generic_types/generic_types.tex

@@ -327 +327 @@
 % \end{lstlisting}
 
-In summation, the \CFA type-system uses \emph{nominal typing} for concrete types, matching with the C type-system and \emph{structural typing} for polymorphic types.
+In summation, the \CFA type-system uses \emph{nominal typing} for concrete types, matching with the C type-system, and \emph{structural typing} for polymorphic types.
 Hence, trait names play no part in type equivalence;
 the names are simply macros for a list of polymorphic assertions, which are expanded at usage sites.
-Nevertheless, trait names form a logical subtype-hierarchy with @dtype@ at the top, where traits often contain overlapping assertions.
+Nevertheless, trait names form a logical subtype-hierarchy with @dtype@ at the top, where traits often contain overlapping assertions, \eg operator @+@.
 Traits are used like interfaces in Java or abstract base-classes in \CC, but without the nominal inheritance-relationships.
 Instead, each polymorphic function (or generic type) defines the structural type needed for its execution (polymorphic type-key), and this key is fulfilled at each call site from the lexical environment, which is similar to Go~\citep{Go} interfaces.
@@ -471 +471 @@
 \begin{lstlisting}
 forall(dtype T) int lexcmp( pair( T *, T * ) * a, pair( T *, T * ) * b, int (* cmp)( T *, T * ) ) {
-        int c = cmp( a->first, b->first );
-        if ( c == 0 ) c = cmp( a->second, b->second );
-        return c;
-}
-\end{lstlisting}
+        return cmp( a->first, b->first ) ? : cmp( a->second, b->second );
+}
+\end{lstlisting}
+%       int c = cmp( a->first, b->first );
+%       if ( c == 0 ) c = cmp( a->second, b->second );
+%       return c;
 Since @pair(T *, T * )@ is a concrete type, there are no implicit parameters passed to @lexcmp@, so the generated code is identical to a function written in standard C using @void *@, yet the \CFA version is type-checked to ensure the fields of both pairs and the arguments to the comparison function match in type.