1 files changed, 77 insertions, 0 deletions
diff --git a/tiger-compiler/lib/misc/symbol.hh b/tiger-compiler/lib/misc/symbol.hh
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+++ b/tiger-compiler/lib/misc/symbol.hh
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+/**
+ ** \file misc/symbol.hh
+ ** \brief Definition of misc::symbol.
+ */
+
+#pragma once
+
+#include <iosfwd>
+#include <set>
+#include <string>
+
+#include <misc/unique.hh>
+
+namespace misc
+{
+  /** \brief Define symbol class.
+   **
+   ** Map any string to a unique reference.
+   ** This allows to avoid an "strcmp()" style comparison of strings:
+   ** reference comparison is much faster.
+   */
+  class symbol : public unique<std::string>
+  {
+    using super_type = unique<std::string>;
+    /// The type "set of strings".
+    using string_set_type = super_type::object_set_type;
+    /// The type for the size of string map.
+    using string_size_type = string_set_type::size_type;
+
+    /** \name Ctor & Dtor.
+     ** \{ */
+  public:
+    /** \brief Construct a symbol.
+     ** \param s referenced string */
+    symbol(const std::string& s);
+    /** \brief Construct a symbol.
+     ** \param s referenced string */
+    symbol(const char* s = "");
+    /** \brief Construct a symbol.
+     ** \param s symbol to copy. */
+    constexpr symbol(const symbol& s) = default;
+    /** \} */
+
+    /** \name Operators.
+     ** \{ */
+  public:
+    /** \brief Assign a symbol to this symbol.
+     ** \param rhs symbol to copy. */
+    symbol& operator=(const symbol& rhs);
+
+    /** \brief Compare two symbol for equality.
+     ** \param rhs string to compare with. */
+    bool operator==(const symbol& rhs) const;
+    /** \brief Compare two symbol for inequality.
+     ** \param rhs string to compare with. *//*  */
+    bool operator!=(const symbol& rhs) const;
+    /** \} */
+
+  public:
+    /** \name Factory methods.
+     ** \{ */
+    /** \brief Create a new unique symbol. */
+    static symbol fresh();
+    /** \brief Create a new unique symbol, forged from \a s. */
+    static symbol fresh(const symbol& s);
+    /** \} */
+  };
+
+  /** \brief Intercept output stream redirection.
+   ** \param ostr the destination output stream
+   ** \param the a reference to the symbol to redirect
+   */
+  std::ostream& operator<<(std::ostream& ostr, const symbol& the);
+
+} // namespace misc
+
+#include <misc/symbol.hxx>