Make containers work with non-copyable elements

It is the first step. The containers can be at least created with
non-copyable structs without compilation errors now.
Fix #69.

source/tanya/container/array.d

@@ -22,6 +22,7 @@ import tanya.memory;
 import tanya.meta.trait;
 import tanya.meta.transform;
 import tanya.range;
+version (unittest) import tanya.test.stub;
 
 /**
  * Random-access range for the $(D_PSYMBOL Array).
@@ -293,7 +294,9 @@ struct Array(T)
      *  init      = Initial value to fill the array with.
      *  allocator = Allocator.
      */
-    this(size_t len, T init, shared Allocator allocator = defaultAllocator)
+    this()(size_t len,
+           auto ref T init,
+           shared Allocator allocator = defaultAllocator)
     {
         this(allocator);
         reserve(len);
@@ -348,15 +351,19 @@ struct Array(T)
         (() @trusted => allocator.deallocate(slice(capacity)))();
     }
 
-    /**
+    static if (isCopyable!T)
-     * Copies the array.
-     */
-    this(this)
     {
-        auto buf = slice(this.length);
+        this(this)
-        this.length_ = capacity_ = 0;
+        {
-        this.data = null;
+            auto buf = slice(this.length);
-        insertBack(buf);
+            this.length_ = capacity_ = 0;
+            this.data = null;
+            insertBack(buf);
+        }
+    }
+    else
+    {
+        @disable this(this);
     }
 
     /**
@@ -1027,7 +1034,7 @@ struct Array(T)
     }
 
     /// ditto
-    Range opIndexAssign(Range value)
+    Range opIndexAssign()(Range value)
     {
         return opSliceAssign(value, 0, length);
     }
@@ -1321,7 +1328,7 @@ struct Array(T)
     }
 
     /// ditto
-    Range opSliceAssign(Range value, size_t i, size_t j) @trusted
+    Range opSliceAssign()(Range value, size_t i, size_t j) @trusted
     in
     {
         assert(i <= j);
@@ -1575,15 +1582,10 @@ struct Array(T)
     assert(v7[].equal(v8[]));
 }
 
+// Destructor can destroy empty arrays
 @nogc nothrow pure @safe unittest
 {
-    static struct SWithDtor
+    auto v = Array!WithDtor();
-    {
-        ~this() @nogc nothrow pure @safe
-        {
-        }
-    }
-    auto v = Array!SWithDtor(); // Destructor can destroy empty arrays.
 }
 
 @nogc nothrow pure @safe unittest
@@ -1594,7 +1596,6 @@ struct Array(T)
     A a1, a2;
     auto v1 = Array!A([a1, a2]);
 
-    // Issue 232: https://issues.caraus.io/issues/232.
     static assert(is(Array!(A*)));
 }
 
@@ -1679,3 +1680,9 @@ struct Array(T)
     }
     func(array);
 }
+
+// Can have non-copyable elements
+@nogc nothrow pure @safe unittest
+{
+    static assert(is(Array!NonCopyable));
+}

source/tanya/container/entry.d

@@ -20,6 +20,7 @@ import tanya.memory.allocator;
 import tanya.meta.trait;
 import tanya.meta.transform;
 import tanya.typecons;
+version (unittest) import tanya.test.stub;
 
 package struct SEntry(T)
 {
@@ -59,12 +60,12 @@ package struct Bucket(K, V = void)
     }
     BucketStatus status = BucketStatus.empty;
 
-    this(ref K key)
+    this()(ref K key)
     {
         this.key = key;
     }
 
-    @property void key(ref K key)
+    @property void key()(ref K key)
     {
         this.key() = key;
         this.status = BucketStatus.used;
@@ -170,7 +171,7 @@ package struct HashArray(alias hasher, K, V = void)
         .swap(this.length, data.length);
     }
 
-    void opAssign(ref typeof(this) that)
+    void opAssign()(ref typeof(this) that)
     {
         this.array = that.array;
         this.lengthIndex = that.lengthIndex;
@@ -326,3 +327,13 @@ package struct HashArray(alias hasher, K, V = void)
         return false;
     }
 }
+
+// Can be constructed with non-copyable key/values
+@nogc nothrow pure @safe unittest
+{
+    static assert(is(Bucket!NonCopyable));
+    static assert(is(Bucket!(NonCopyable, NonCopyable)));
+
+    static assert(is(HashArray!((ref NonCopyable) => 0U, NonCopyable)));
+    static assert(is(HashArray!((ref NonCopyable) => 0U, NonCopyable, NonCopyable)));
+}

source/tanya/container/hashtable.d

@@ -22,6 +22,7 @@ import tanya.memory;
 import tanya.meta.trait;
 import tanya.meta.transform;
 import tanya.range.primitive;
+version (unittest) import tanya.test.stub;
 
 /**
  * Bidirectional range whose element type is a tuple of a key and the
@@ -68,7 +69,7 @@ struct Range(T)
         return this.dataRange.empty();
     }
 
-    @property void popFront()
+    void popFront()
     in
     {
         assert(!empty);
@@ -87,7 +88,7 @@ struct Range(T)
         while (!empty && dataRange.front.status != BucketStatus.used);
     }
 
-    @property void popBack()
+    void popBack()
     in
     {
         assert(!empty);
@@ -759,7 +760,7 @@ if (isHashFunction!(hasher, Key))
      *
      * Returns: The number of the inserted elements with a unique key.
      */
-    size_t insert(ref KeyValue keyValue)
+    size_t insert()(ref KeyValue keyValue)
     {
         auto e = ((ref v) @trusted => &this.data.insert(v))(keyValue.key);
         size_t inserted;
@@ -773,7 +774,7 @@ if (isHashFunction!(hasher, Key))
     }
 
     /// ditto
-    size_t insert(KeyValue keyValue)
+    size_t insert()(KeyValue keyValue)
     {
         auto e = ((ref v) @trusted => &this.data.insert(v))(keyValue.key);
         size_t inserted;
@@ -1197,3 +1198,16 @@ if (isHashFunction!(hasher, Key))
     static assert(is(typeof("asdf" in HashTable!(String, int)())));
     static assert(is(typeof(HashTable!(String, int)()["asdf"])));
 }
+
+// Can have non-copyable keys and elements
+@nogc nothrow pure @safe unittest
+{
+    @NonCopyable @Hashable
+    static struct S
+    {
+        mixin StructStub;
+    }
+    static assert(is(HashTable!(S, int)));
+    static assert(is(HashTable!(int, S)));
+    static assert(is(HashTable!(S, S)));
+}

source/tanya/container/list.d

@@ -23,6 +23,7 @@ import tanya.meta.trait;
 import tanya.meta.transform;
 import tanya.range.array;
 import tanya.range.primitive;
+version (unittest) import tanya.test.stub;
 
 /**
  * Forward range for the $(D_PSYMBOL SList).
@@ -155,8 +156,9 @@ struct SList(T)
      *  init      = Initial value to fill the list with.
      *  allocator = Allocator.
      */
-    this(size_t len, T init, shared Allocator allocator = defaultAllocator)
+    this()(size_t len,
-    @trusted
+           auto ref T init,
+           shared Allocator allocator = defaultAllocator)
     {
         this(allocator);
         if (len == 0)
@@ -182,7 +184,18 @@ struct SList(T)
     /// ditto
     this(size_t len, shared Allocator allocator = defaultAllocator)
     {
-        this(len, T.init, allocator);
+        this(allocator);
+        if (len == 0)
+        {
+            return;
+        }
+
+        Entry* next = this.head = allocator.make!Entry();
+        foreach (i; 1 .. len)
+        {
+            next.next = allocator.make!Entry();
+            next = next.next;
+        }
     }
 
     ///
@@ -271,14 +284,18 @@ struct SList(T)
         clear();
     }
 
-    /**
+    static if (isCopyable!T)
-     * Copies the list.
-     */
-    this(this)
     {
-        auto list = typeof(this)(this[], this.allocator);
+        this(this)
-        this.head = list.head;
+        {
-        list.head = null;
+            auto list = typeof(this)(this[], this.allocator);
+            this.head = list.head;
+            list.head = null;
+        }
+    }
+    else
+    {
+        @disable this(this);
     }
 
     ///
@@ -512,7 +529,7 @@ struct SList(T)
     }
 
     /// ditto
-    size_t insertBefore(Range r, ref T el) @trusted
+    size_t insertBefore()(Range r, ref T el) @trusted
     in
     {
         assert(checkRangeBelonging(r));
@@ -1120,8 +1137,9 @@ struct DList(T)
      *  init      = Initial value to fill the list with.
      *  allocator = Allocator.
      */
-    this(size_t len, T init, shared Allocator allocator = defaultAllocator)
+    this()(size_t len,
-    @trusted
+           auto ref T init,
+           shared Allocator allocator = defaultAllocator)
     {
         this(allocator);
         if (len == 0)
@@ -1150,7 +1168,20 @@ struct DList(T)
     /// ditto
     this(size_t len, shared Allocator allocator = defaultAllocator)
     {
-        this(len, T.init, allocator);
+        this(allocator);
+        if (len == 0)
+        {
+            return;
+        }
+
+        Entry* next = this.head = allocator.make!Entry();
+        foreach (i; 1 .. len)
+        {
+            next.next = allocator.make!Entry();
+            next.next.prev = next;
+            next = next.next;
+        }
+        this.tail = next;
     }
 
     ///
@@ -1242,15 +1273,19 @@ struct DList(T)
         clear();
     }
 
-    /**
+    static if (isCopyable!T)
-     * Copies the list.
-     */
-    this(this)
     {
-        auto list = typeof(this)(this[], this.allocator);
+        this(this)
-        this.head = list.head;
+        {
-        this.tail = list.tail;
+            auto list = typeof(this)(this[], this.allocator);
-        list.head = list .tail = null;
+            this.head = list.head;
+            this.tail = list.tail;
+            list.head = list .tail = null;
+        }
+    }
+    else
+    {
+        @disable this(this);
     }
 
     ///
@@ -1641,7 +1676,7 @@ struct DList(T)
     }
 
     /// ditto
-    size_t insertBefore(Range r, ref T el) @trusted
+    size_t insertBefore()(Range r, ref T el) @trusted
     in
     {
         assert(checkRangeBelonging(r));
@@ -1758,7 +1793,7 @@ struct DList(T)
     }
 
     /// ditto
-    size_t insertAfter(Range r, ref T el) @trusted
+    size_t insertAfter()(Range r, ref T el) @trusted
     in
     {
         assert(checkRangeBelonging(r));
@@ -2355,3 +2390,10 @@ struct DList(T)
     assert(!l1.remove(r).empty);
     assert(l1 == l2);
 }
+
+// Can have non-copyable elements
+@nogc nothrow pure @safe unittest
+{
+    static assert(is(SList!NonCopyable));
+    static assert(is(DList!NonCopyable));
+}

source/tanya/container/set.d

@@ -22,6 +22,7 @@ import tanya.memory;
 import tanya.meta.trait;
 import tanya.meta.transform;
 import tanya.range.primitive;
+version (unittest) import tanya.test.stub;
 
 /**
  * Bidirectional range that iterates over the $(D_PSYMBOL Set)'s values.
@@ -67,7 +68,7 @@ struct Range(T)
         return this.dataRange.empty();
     }
 
-    @property void popFront()
+    void popFront()
     in
     {
         assert(!empty);
@@ -86,7 +87,7 @@ struct Range(T)
         while (!empty && dataRange.front.status != BucketStatus.used);
     }
 
-    @property void popBack()
+    void popBack()
     in
     {
         assert(!empty);
@@ -459,7 +460,7 @@ if (isHashFunction!(hasher, T))
      *
      * Returns: Amount of new elements inserted.
      */
-    size_t insert(ref T value)
+    size_t insert()(ref T value)
     {
         auto e = ((ref v) @trusted => &this.data.insert(v))(value);
         if (e.status != BucketStatus.used)
@@ -470,7 +471,7 @@ if (isHashFunction!(hasher, T))
         return 0;
     }
 
-    size_t insert(T value)
+    size_t insert()(T value)
     {
         auto e = ((ref v) @trusted => &this.data.insert(v))(value);
         if (e.status != BucketStatus.used)
@@ -773,3 +774,14 @@ if (isHashFunction!(hasher, T))
 {
     static assert(is(Set!(int, (const ref x) => cast(size_t) x)));
 }
+
+// Can have non-copyable elements
+@nogc nothrow pure @safe unittest
+{
+    @NonCopyable @Hashable
+    static struct S
+    {
+        mixin StructStub;
+    }
+    static assert(is(Set!S));
+}

source/tanya/hash/lookup.d

@@ -16,6 +16,7 @@ module tanya.hash.lookup;
 
 import tanya.meta.trait;
 import tanya.range.primitive;
+version (unittest) import tanya.test.stub;
 
 private struct FNV
 {
@@ -146,14 +147,6 @@ version (unittest)
                                ~ r10!x ~ r10!x ~ r10!x ~ r10!x ~ r10!x;
     enum string r500(string x) = r100!x ~ r100!x ~ r100!x ~ r100!x ~ r100!x;
 
-    private static struct ToHash
-    {
-        size_t toHash() const @nogc nothrow pure @safe
-        {
-            return 0;
-        }
-    }
-
     private static struct HashRange
     {
         string fo = "fo";
@@ -178,9 +171,9 @@ version (unittest)
     {
         bool empty_;
 
-        @property ToHash front() const @nogc nothrow pure @safe
+        @property Hashable front() const @nogc nothrow pure @safe
         {
-            return ToHash();
+            return Hashable();
         }
 
         void popFront() @nogc nothrow pure @safe
@@ -199,7 +192,7 @@ version (unittest)
 @nogc nothrow pure @safe unittest
 {
     assert(hash(null) == 0);
-    assert(hash(ToHash()) == 0U);
+    assert(hash(Hashable()) == 0U);
     assert(hash('a') == 'a');
 }
 

source/tanya/test/stub.d

@@ -91,7 +91,7 @@ struct WithLvalueElements
 mixin template InputRangeStub(E = int)
 {
     import tanya.meta.metafunction : Alias;
-    import tanya.meta.trait : getUDAs, hasUDA;
+    import tanya.meta.trait : evalUDA, getUDAs, hasUDA;
 
     /*
      * Aliases for the attribute lookups to access them faster
@@ -279,6 +279,9 @@ mixin template RandomAccessRangeStub(E = int)
 
 /**
  * Struct with a disabled postblit constructor.
+ *
+ * $(D_PSYMBOL NonCopyable) can be used as an attribute for
+ * $(D_PSYMBOL StructStub) or as a standalone type.
  */
 struct NonCopyable
 {
@@ -288,10 +291,14 @@ struct NonCopyable
 /**
  * Struct with an elaborate destructor.
  *
- * The constructor of $(D_PSYMBOL WithDtor) accepts an additional `counter`
+ * $(D_PSYMBOL WithDtor) can be used as an attribute for
- * argument, which is incremented by the destructor. $(D_PSYMBOL WithDtor)
+ * $(D_PSYMBOL StructStub) or as a standalone type.
- * stores a pointer to the passed variable, so the variable can be
+ *
- * investigated after the struct isn't available anymore.
+ * When used as a standalone object the constructor of $(D_PSYMBOL WithDtor)
+ * accepts an additional `counter` argument, which is incremented by the
+ * destructor. $(D_PSYMBOL WithDtor) stores a pointer to the passed variable,
+ * so the variable can be investigated after the struct isn't available
+ * anymore.
  */
 struct WithDtor
 {
@@ -310,3 +317,57 @@ struct WithDtor
         }
     }
 }
+
+/**
+ * Struct supporting hashing.
+ *
+ * $(D_PSYMBOL Hashable) can be used as an attribute for
+ * $(D_PSYMBOL StructStub) or as a standalone type.
+ *
+ * The constructor accepts an additional parameter, which is returned by the
+ * `toHash()`-function. `0U` is returned if no hash value is given.
+ */
+struct Hashable
+{
+    size_t hash;
+
+    size_t toHash() const @nogc nothrow pure @safe
+    {
+        return this.hash;
+    }
+}
+
+/**
+ * Generates a $(D_KEYWORD struct) with common functionality.
+ *
+ * To specify the needed functionality use user-defined attributes on the
+ * $(D_KEYWORD struct) $(D_PSYMBOL StructStub) is mixed in.
+ *
+ * Supported attributes are: $(D_PSYMBOL NonCopyable), $(D_PSYMBOL Hashable),
+ * $(D_PSYMBOL WithDtor).
+ */
+mixin template StructStub()
+{
+    import tanya.meta.trait : evalUDA, getUDAs, hasUDA;
+
+    static if (hasUDA!(typeof(this), NonCopyable))
+    {
+        @disable this(this);
+    }
+
+    private alias Hashable = getUDAs!(typeof(this), .Hashable);
+    static if (Hashable.length > 0)
+    {
+        size_t toHash() const @nogc nothrow pure @safe
+        {
+            return evalUDA!(Hashable[0]).hash;
+        }
+    }
+
+    static if (hasUDA!(typeof(this), WithDtor))
+    {
+        ~this() @nogc nothrow pure @safe
+        {
+        }
+    }
+}

source/tanya/typecons.d

@@ -503,30 +503,16 @@ struct Option(T)
 // Returns default value
 @nogc nothrow pure @safe unittest
 {
-    {
+    int i = 5;
-        int i = 5;
+    assert(((ref e) => e)(Option!int().or(i)) == 5);
-        assert(((ref e) => e)(Option!int().or(i)) == 5);
-    }
 }
 
 // Implements toHash() for nothing
 @nogc nothrow pure @safe unittest
 {
-    static struct ToHash
+    alias OptionT = Option!Hashable;
-    {
+    assert(OptionT().toHash() == 0U);
-        size_t toHash() const @nogc nothrow pure @safe
+    assert(OptionT(Hashable(1U)).toHash() == 1U);
-        {
-            return 1U;
-        }
-    }
-    {
-        Option!ToHash toHash;
-        assert(toHash.toHash() == 0U);
-    }
-    {
-        auto toHash = Option!ToHash(ToHash());
-        assert(toHash.toHash() == 1U);
-    }
 }
 
 /**