Implement pure onOutOfMemory

source/tanya/exception.d

@@ -0,0 +1,66 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Common exceptions and errors.
+ *
+ * Copyright: Eugene Wissner 2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ * Source: $(LINK2 https://github.com/caraus-ecms/tanya/blob/master/source/tanya/exception.d,
+ *                 tanya/exception.d)
+ */
+module tanya.exception;
+
+import tanya.conv;
+import tanya.memory;
+
+/**
+ * Error thrown if memory allocation fails.
+ */
+final class OutOfMemoryError : Error
+{
+    /**
+     * Constructs new error.
+     *
+     * Params:
+     *  msg  = The message for the exception.
+     *  file = The file where the exception occurred.
+     *  line = The line number where the exception occurred.
+     *  next = The previous exception in the chain of exceptions, if any.
+     */
+    this(string msg = "Out of memory",
+         string file = __FILE__,
+         size_t line = __LINE__,
+         Throwable next = null) @nogc nothrow pure @safe
+    {
+        super(msg, file, line, next);
+    }
+
+    /// ditto
+    this(string msg,
+         Throwable next,
+         string file = __FILE__,
+         size_t line = __LINE__) @nogc nothrow pure @safe
+    {
+        super(msg, file, line, next);
+    }
+}
+
+/**
+ * Allocates $(D_PSYMBOL OutOfMemoryError) in a static storage and throws it.
+ *
+ * Params:
+ *  msg = Custom error message.
+ *
+ * Throws: $(D_PSYMBOL OutOfMemoryError).
+ */
+void onOutOfMemoryError(string msg = "Out of memory")
+@nogc nothrow pure @trusted
+{
+    static ubyte[stateSize!OutOfMemoryError] memory;
+    alias PureType = OutOfMemoryError function(string) @nogc nothrow pure;
+    throw (cast(PureType) () => emplace!OutOfMemoryError(memory))(msg);
+}