From 549e1b6029efc161e5346ef9af8ed750bd02780d Mon Sep 17 00:00:00 2001
From: Dmitry Atamanov <dataman@tutanota.com>
Date: Sat, 4 Mar 2023 21:17:37 +0500
Subject: [PATCH] Added `std::collections::enummap`.

---
 lib/std/collections/enummap.c3          | 18 +++++++++++++++
 test/unit/stdlib/collections/enummap.c3 | 29 +++++++++++++++++++++++++
 2 files changed, 47 insertions(+)
 create mode 100644 lib/std/collections/enummap.c3
 create mode 100644 test/unit/stdlib/collections/enummap.c3

diff --git a/lib/std/collections/enummap.c3 b/lib/std/collections/enummap.c3
new file mode 100644
index 000000000..59239a1a4
--- /dev/null
+++ b/lib/std/collections/enummap.c3
@@ -0,0 +1,18 @@
+module std::collections::enummap<Enum, ValueType>;
+
+struct EnumMap
+{
+    ValueType[Enum.len] values;
+}
+
+fn void EnumMap.init(EnumMap* this, ValueType init_value)
+{
+    foreach(&a : this.values)
+    {
+        *a = init_value;
+    }
+}
+
+fn uint EnumMap.len(EnumMap* this) @operator(len) => this.values.len;
+fn ValueType EnumMap.get(EnumMap* this, Enum key) @operator([]) => this.values[key.ordinal];
+fn void EnumMap.set(EnumMap* this, Enum key, ValueType value) @operator([]=) => this.values[key.ordinal] = value;
diff --git a/test/unit/stdlib/collections/enummap.c3 b/test/unit/stdlib/collections/enummap.c3
new file mode 100644
index 000000000..97f2f0c2d
--- /dev/null
+++ b/test/unit/stdlib/collections/enummap.c3
@@ -0,0 +1,29 @@
+module enummap_test @test;
+import std::collections::enummap;
+
+enum FooEnum
+{
+    ONE,
+    TWO,
+    THREE,
+}
+
+typedef FooEnumMap = EnumMap<FooEnum, uint>;
+
+fn void! enums()
+{
+    FooEnumMap nm;
+    nm.set(ONE, 1);
+    nm.set(TWO, 2);
+    nm.set(THREE, 3);
+
+    assert(nm[FooEnum.ONE] == 1);
+    assert(nm[FooEnum.TWO] == 2);
+    assert(nm[FooEnum.THREE] == 3);
+
+    nm.init(0);
+
+    assert(nm[FooEnum.ONE] == 0);
+    assert(nm[FooEnum.TWO] == 0);
+    assert(nm[FooEnum.THREE] == 0);
+}