add antlr

lib/antlr4/include/misc/Interval.h

@@ -0,0 +1,84 @@
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#pragma once
+
+#include "antlr4-common.h"
+
+namespace antlr4 {
+namespace misc {
+
+  // Helpers to convert certain unsigned symbols (e.g. Token::EOF) to their original numeric value (e.g. -1)
+  // and vice versa. This is needed mostly for intervals to keep their original order and for toString()
+  // methods to print the original numeric value (e.g. for tests).
+  size_t numericToSymbol(ssize_t v);
+  ssize_t symbolToNumeric(size_t v);
+
+  /// An immutable inclusive interval a..b
+  class ANTLR4CPP_PUBLIC Interval {
+  public:
+    static const Interval INVALID;
+
+    // Must stay signed to guarantee the correct sort order.
+    ssize_t a;
+    ssize_t b;
+
+    Interval();
+    explicit Interval(size_t a_, size_t b_); // For unsigned -> signed mappings.
+    Interval(ssize_t a_, ssize_t b_);
+
+    /// return number of elements between a and b inclusively. x..x is length 1.
+    ///  if b < a, then length is 0.  9..10 has length 2.
+    size_t length() const;
+
+    bool operator == (const Interval &other) const;
+
+    size_t hashCode() const;
+
+    /// <summary>
+    /// Does this start completely before other? Disjoint </summary>
+    bool startsBeforeDisjoint(const Interval &other) const;
+
+    /// <summary>
+    /// Does this start at or before other? Nondisjoint </summary>
+    bool startsBeforeNonDisjoint(const Interval &other) const;
+
+    /// <summary>
+    /// Does this.a start after other.b? May or may not be disjoint </summary>
+    bool startsAfter(const Interval &other) const;
+
+    /// <summary>
+    /// Does this start completely after other? Disjoint </summary>
+    bool startsAfterDisjoint(const Interval &other) const;
+
+    /// <summary>
+    /// Does this start after other? NonDisjoint </summary>
+    bool startsAfterNonDisjoint(const Interval &other) const;
+
+    /// <summary>
+    /// Are both ranges disjoint? I.e., no overlap? </summary>
+    bool disjoint(const Interval &other) const;
+
+    /// <summary>
+    /// Are two intervals adjacent such as 0..41 and 42..42? </summary>
+    bool adjacent(const Interval &other) const;
+
+    bool properlyContains(const Interval &other) const;
+
+    /// <summary>
+    /// Return the interval computed from combining this and other </summary>
+    Interval Union(const Interval &other) const;
+
+    /// <summary>
+    /// Return the interval in common between this and o </summary>
+    Interval intersection(const Interval &other) const;
+
+    std::string toString() const;
+
+  private:
+  };
+
+} // namespace atn
+} // namespace antlr4