| Index: tests/language/generic_functions_test.dart
|
| diff --git a/tests/language/generic_functions_test.dart b/tests/language/generic_functions_test.dart
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..6c2942c5f5b0a7bbf49408d150dbf2bc821f8a24
|
| --- /dev/null
|
| +++ b/tests/language/generic_functions_test.dart
|
| @@ -0,0 +1,109 @@
|
| +// Copyright (c) 2016, the Dart project authors. Please see the AUTHORS file
|
| +// for details. All rights reserved. Use of this source code is governed by a
|
| +// BSD-style license that can be found in the LICENSE file.
|
| +//
|
| +// DartOptions=--generic-method-syntax
|
| +// AnalyzerOptions=--options=./generic_functions_test.dart
|
| +
|
| +import "package:expect/expect.dart";
|
| +
|
| +// Dart test verifying that the parser can handle type parameterization of
|
| +// function declarations and function invocations. Variant of code from
|
| +// DEP #22, adjusted to use generic top level functions.
|
| +
|
| +class BinaryTreeNode<K extends Comparable<K>, V> {
|
| + final K _key;
|
| + final V _value;
|
| + final BinaryTreeNode<K, V> _left;
|
| + final BinaryTreeNode<K, V> _right;
|
| +
|
| + BinaryTreeNode(this._key, this._value,
|
| + {BinaryTreeNode<K, V> left: null, BinaryTreeNode<K, V> right: null}) :
|
| + _left = left, _right = right;
|
| +
|
| + BinaryTreeNode<K, V> insert(K key, V value) {
|
| + int c = key.compareTo(_key);
|
| + if (c == 0) return this;
|
| + var _insert = (BinaryTreeNode<K, V> t, K key, V value) =>
|
| + insertOpt<K, V>(t, key, value);
|
| + BinaryTreeNode<K, V> left = _left;
|
| + BinaryTreeNode<K, V> right = _right;
|
| + if (c < 0) {
|
| + left = _insert(_left, key, value);
|
| + } else {
|
| + right = _insert(_right, key, value);
|
| + }
|
| + return new BinaryTreeNode<K, V>(_key, _value, left: left, right: right);
|
| + }
|
| +
|
| + BinaryTreeNode<K, U> map<U>(U f(V x)){
|
| + var _map = (BinaryTreeNode<K, V> t, U f(V x)) => mapOpt<K, V, U>(t, f);
|
| + return new BinaryTreeNode<K, U>(
|
| + _key,
|
| + f(_value),
|
| + left: _map(_left, f),
|
| + right: _map(_right, f));
|
| + }
|
| +
|
| + S foldPre<S>(S init, S f(V t, S s)) {
|
| + var _fold = (BinaryTreeNode<K, V> t, S s, S f(V t, S s)) =>
|
| + foldPreOpt<K, V, S>(t, s, f);
|
| + S s = init;
|
| + s = f(_value, s);
|
| + s = _fold(_left, s, f);
|
| + s = _fold(_right, s, f);
|
| + return s;
|
| + }
|
| +}
|
| +
|
| +// Use fresh type variables.
|
| +BinaryTreeNode<K2, V2> insertOpt<K2 extends Comparable<K2>, V2>(
|
| + BinaryTreeNode<K2, V2> t, K2 key, V2 value) {
|
| + return (t == null) ? new BinaryTreeNode(key, value) : t.insert(key, value);
|
| +}
|
| +
|
| +// Reuse type variables [K], [V] to test shadowing.
|
| +BinaryTreeNode<K, U> mapOpt<K extends Comparable<K>, V, U>(
|
| + BinaryTreeNode<K, V> t, U f(V x)) {
|
| + return (t == null) ? null : t.map<U>(f);
|
| +}
|
| +
|
| +// Use fresh [K2], shadowing [V].
|
| +S foldPreOpt<K2 extends Comparable<K2>, V, S>(
|
| + BinaryTreeNode<K2, V> t, S init, S f(V t, S s)) {
|
| + return (t == null) ? init : t.foldPre<S>(init, f);
|
| +}
|
| +
|
| +class BinaryTree<K extends Comparable<K>, V> {
|
| + final BinaryTreeNode<K, V> _root;
|
| +
|
| + BinaryTree._internal(this._root);
|
| + BinaryTree.empty() : this._internal(null);
|
| +
|
| + BinaryTree<K, V> insert(K key, V value) {
|
| + BinaryTreeNode<K, V> root = insertOpt<K, V>(_root, key, value);
|
| + return new BinaryTree<K, V>._internal(root);
|
| + }
|
| +
|
| + BinaryTree<K, U> map<U>(U f(V x)) {
|
| + BinaryTreeNode<K, U> root = mapOpt<K, V, U>(_root, f);
|
| + return new BinaryTree<K, U>._internal(root);
|
| + }
|
| +
|
| + S foldPre<S>(S init, S f(V t, S s)) {
|
| + return foldPreOpt<K, V, S>(_root, init, f);
|
| + }
|
| +}
|
| +
|
| +main() {
|
| + BinaryTree<num, String> sT = new BinaryTree<num, String>.empty();
|
| +
|
| + sT = sT.insert(0, "");
|
| + sT = sT.insert(1, " ");
|
| + sT = sT.insert(2, " ");
|
| + sT = sT.insert(3, " ");
|
| +
|
| + BinaryTree<num, num> iT = sT.map<num>((String s) => s.length);
|
| +
|
| + Expect.equals(iT.foldPre<num>(0, (int i, num s) => i + s), 6);
|
| +}
|
|
|