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Diffstat (limited to 'build/string-table')
-rw-r--r-- | build/string-table | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/build/string-table b/build/string-table new file mode 100644 index 0000000..522476f --- /dev/null +++ b/build/string-table @@ -0,0 +1,90 @@ +// file : build/string-table -*- C++ -*- +// copyright : Copyright (c) 2014-2015 Code Synthesis Tools CC +// license : MIT; see accompanying LICENSE file + +#ifndef BUILD_STRING_TABLE +#define BUILD_STRING_TABLE + +#include <vector> +#include <string> +#include <unordered_map> + +#include <build/map-key> + +namespace build +{ + // A pool of strings and, optionally, other accompanying data in which + // each entry is assigned an individual index (or id) of type I (e.g., + // uint8_t, uint16_t, etc., depending on how many entries are expected). + // Index value 0 is reserved to indicate the "no entry" condition. + // + template <typename I, typename D> + struct string_table_element + { + const I i; + const D d; + }; + + template <typename I> + struct string_table_element<I, std::string> + { + const I i; + const std::string d; + }; + + template <typename D> + struct string_table_traits + { + // By default, look for the key() function in D. But you can + // also specialize this class template. + // + static const std::string& + key (const D& d) {return d.key ();} + }; + + template <> + struct string_table_traits<std::string> + { + static const std::string& + key (const std::string& d) {return d;} + }; + + template <typename I, typename D = std::string> + struct string_table + { + // Insert new entry unless one already exists. + // + I + insert (const D&); + + // Find existing. + // + I + find (const std::string& k) const + { + auto i (map_.find (key_type (&k))); + return i != map_.end () ? i->second.i : 0; + } + + // Reverse lookup. + // + const D& + operator[] (I i) const {assert (i > 0); return vec_[i - 1]->second.d;} + + I + size () const {return static_cast<I> (vec_.size ());} + + private: + using key_type = map_key<std::string>; + using value_type = string_table_element<I, D>; + using map_type = std::unordered_map<key_type, value_type>; + using traits = string_table_traits<D>; + + map_type map_; + std::vector<typename map_type::const_iterator> vec_; + }; +} + +#include <build/string-table.txx> + +#endif // BUILD_STRING_TABLE |