Changeset 108f3cdb for src/Common/utility.h

Timestamp:

Sep 12, 2017, 10:45:01 AM (7 years ago)

Author:

Rob Schluntz <rschlunt@…>

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:

93389c1

Parents:

1395748

Message:

Fix generation of assignment and autogenerate constructors and destructors for opaque type declarations

File:

• src/Common/utility.h (modified) (1 diff)

src/Common/utility.h

@@ -370 +370 @@
 }
 
+// -----------------------------------------------------------------------------
+// Helper struct and function to support
+// for ( val : lazy_map( container1, f ) ) {}
+// syntax to have a for each that iterates a container, mapping each element by applying f
+template< typename T, typename Func >
+struct lambda_iterate_t {
+        T & ref;
+        Func f;
+
+        struct iterator {
+                typedef decltype(begin(ref)) Iter;
+                Iter it;
+                Func f;
+                iterator( Iter it, Func f ) : it(it), f(f) {}
+                iterator & operator++() {
+                        ++it; return *this;
+                }
+                bool operator!=( const iterator &other ) const { return it != other.it; }
+                auto operator*() const -> decltype(f(*it)) { return f(*it); }
+        };
+
+        lambda_iterate_t( T & ref, Func f ) : ref(ref), f(f) {}
+
+        auto begin() const -> decltype(iterator(std::begin(ref), f)) { return iterator(std::begin(ref), f); }
+        auto end() const   -> decltype(iterator(std::end(ref), f)) { return iterator(std::end(ref), f); }
+};
+
+template< typename... Args >
+lambda_iterate_t<Args...> lazy_map( Args &&... args ) {
+        return lambda_iterate_t<Args...>(std::forward<Args>( args )...);
+}
+
+
+
 // Local Variables: //
 // tab-width: 4 //