Changeset 184557e for src/Common/PersistentMap.h

Timestamp:

Jul 6, 2018, 5:10:14 PM (6 years ago)

Author:

Aaron Moss <a3moss@…>

Branches:

new-env

Children:

5c14030

Parents:

b21c77a

Message:

First draft of persistent-hash-based TypeEnvironment?

File:

• src/Common/PersistentMap.h (modified) (2 diffs)

src/Common/PersistentMap.h

@@ -114 +114 @@
         }
 
+        /// Non-initializing constructor; should call init() before use
+        PersistentMap( Mode m ) : data(), mode(m) {}
+
         PersistentMap( Mode m, Base&& b ) : data(), mode(m) {
                 assertf(m == BASE, "invalid mode");
@@ -420 +423 @@
                 }
         }
+
+        /// Applies the function `f` to all elements of the map, returning a pointer to the updated map.
+        /// `f` should take two parameters, `const Key&` and `Val&`, returning option<Val> filled with 
+        /// the previous value if mutated, an empty option<Val> otherwise.
+        /// NOTE: when porting to C++17, this should work fine with std::optional
+        template<typename F>
+        Self* apply_to_all(F&& f) {
+                // reset to root and exit early if no change
+                if ( rerooted().empty() ) return this;
+
+                // remove map from self
+                Base base_map = take_as<Base>();
+                reset_as_base();
+
+                // apply all edits
+                Self* next_edit = this;
+                for ( auto& entry : base_map ) {
+                        auto res = f( entry.first, entry.second );
+                        if ( res ) {
+                                // entry has been mutated; reset next_edit node as mutation
+                                Self* new_node = new Self{ BASE };
+                                next_edit->init<Ins>( new_node, entry.first, *std::move(res) );
+                                next_edit->mode = UPD;
+                                next_edit = new_node;
+                        }
+                }
+
+                // set map into final node and return
+                next_edit->init<Base>( std::move(base_map) );
+                return next_edit;
+        }
+
+        /// Applies the function `f` to all elements of the map.
+        /// `f` should take two parameters, `const Key&` and `const Val&`.
+        template<typename F>
+        void apply_to_all(F&& f) const {
+                for ( const auto& entry : rerooted() ) { f( entry.first, entry.second ); }
+        }
 };