1 files changed, 77 insertions, 0 deletions
diff --git a/src/deps/skia/include/private/SkSLProgramElement.h b/src/deps/skia/include/private/SkSLProgramElement.h
new file mode 100644
index 000000000..88c4129ee
--- /dev/null
+++ b/src/deps/skia/include/private/SkSLProgramElement.h
@@ -0,0 +1,77 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SKSL_PROGRAMELEMENT
+#define SKSL_PROGRAMELEMENT
+
+#include "include/private/SkSLIRNode.h"
+
+#include <memory>
+
+namespace SkSL {
+
+/**
+ * Represents a top-level element (e.g. function or global variable) in a program.
+ */
+class ProgramElement : public IRNode {
+public:
+    enum class Kind {
+        kExtension = 0,
+        kFunction,
+        kFunctionPrototype,
+        kGlobalVar,
+        kInterfaceBlock,
+        kModifiers,
+        kStructDefinition,
+
+        kFirst = kExtension,
+        kLast = kStructDefinition
+    };
+
+    ProgramElement(int offset, Kind kind)
+        : INHERITED(offset, (int) kind) {
+        SkASSERT(kind >= Kind::kFirst && kind <= Kind::kLast);
+    }
+
+    Kind kind() const {
+        return (Kind) fKind;
+    }
+
+    /**
+     *  Use is<T> to check the type of a program element.
+     *  e.g. replace `el.kind() == ProgramElement::Kind::kExtension` with `el.is<Extension>()`.
+     */
+    template <typename T>
+    bool is() const {
+        return this->kind() == T::kProgramElementKind;
+    }
+
+    /**
+     *  Use as<T> to downcast program elements. e.g. replace `(Extension&) el` with
+     * `el.as<Extension>()`.
+     */
+    template <typename T>
+    const T& as() const {
+        SkASSERT(this->is<T>());
+        return static_cast<const T&>(*this);
+    }
+
+    template <typename T>
+    T& as() {
+        SkASSERT(this->is<T>());
+        return static_cast<T&>(*this);
+    }
+
+    virtual std::unique_ptr<ProgramElement> clone() const = 0;
+
+private:
+    using INHERITED = IRNode;
+};
+
+}  // namespace SkSL
+
+#endif