diff options
author | Boris Kolpackov <boris@codesynthesis.com> | 2015-02-23 16:16:23 +0200 |
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committer | Boris Kolpackov <boris@codesynthesis.com> | 2015-02-23 16:16:23 +0200 |
commit | dea0d0913711f23fff3b902e3aa6006c6b54905a (patch) | |
tree | 3d1c3802af8bf68566e02683347f4251fa6d603e /build/prefix-map | |
parent | e5fedf8a485d7b1b7d26e08557ca40c863d3255b (diff) |
Clean up file names
Diffstat (limited to 'build/prefix-map')
-rw-r--r-- | build/prefix-map | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/build/prefix-map b/build/prefix-map new file mode 100644 index 0000000..d2ca9be --- /dev/null +++ b/build/prefix-map @@ -0,0 +1,140 @@ +// file : build/prefix-map -*- C++ -*- +// copyright : Copyright (c) 2014-2015 Code Synthesis Tools CC +// license : MIT; see accompanying LICENSE file + +#ifndef BUILD_PREFIX_MAP +#define BUILD_PREFIX_MAP + +#include <map> +#include <string> +#include <utility> // move() +#include <algorithm> // min() + +namespace build +{ + template <typename K> + struct compare_prefix; + + template <typename C> + struct compare_prefix<std::basic_string<C>> + { + typedef std::basic_string<C> K; + + typedef C char_type; + typedef typename K::size_type size_type; + typedef typename K::traits_type traits_type; + + explicit + compare_prefix (C d): d_ (d) {} + + bool + operator() (const K& x, const K& y) const + { + return compare (x.c_str (), x.size (), y.c_str (), y.size ()) < 0; + } + + // Note: doesn't check for k.size () being at least p.size (). + // + bool + prefix (const K& p, const K& k) const + { + size_type pn (p.size ()); + return compare ( + p.c_str (), pn, k.c_str (), pn == k.size () ? pn : pn + 1) == 0; + } + + int + compare (const C* x, size_type xn, + const C* y, size_type yn) const + { + size_type n (std::min (xn, yn)); + int r (traits_type::compare (x, y, n)); + + if (r == 0) + { + // Pretend there is the delimiter characters at the end of the + // shorter string. + // + char xc (xn > n ? x[n] : (xn++, d_)); + char yc (yn > n ? y[n] : (yn++, d_)); + r = traits_type::compare (&xc, &yc, 1); + + // If we are still equal, then compare the lengths. + // + if (r == 0) + r = (xn == yn ? 0 : (xn < yn ? -1 : 1)); + } + + return r; + } + + private: + C d_; + }; + + // A map of hierarchical "paths", e.g., 'foo.bar' or 'foo/bar' with + // the ability to retrieve a range of entries that have a specific + // prefix. The '.' and '/' above are the delimiter characters. + // + // Implementation-wise, the idea is to pretend that each key ends + // with the delimiter. This way we automatically avoid matching + // 'foobar' as having a prefix 'foo'. + // + template <typename M> + struct prefix_map_common: M + { + typedef M map_type; + typedef typename map_type::key_type key_type; + typedef typename map_type::value_type value_type; + typedef typename map_type::key_compare compare_type; + typedef typename compare_type::char_type char_type; + + typedef typename map_type::iterator iterator; + typedef typename map_type::const_iterator const_iterator; + + explicit + prefix_map_common (char_type delimiter) + : map_type (compare_type (delimiter)) {} + + prefix_map_common (std::initializer_list<value_type> init, + char_type delimiter) + : map_type (std::move (init), compare_type (delimiter)) {} + + std::pair<iterator, iterator> + find (const key_type&); + + std::pair<const_iterator, const_iterator> + find (const key_type&) const; + }; + + template <typename M, typename prefix_map_common<M>::char_type D = 0> + struct prefix_map_impl: prefix_map_common<M> + { + typedef typename prefix_map_common<M>::value_type value_type; + + prefix_map_impl (): prefix_map_common<M> (D) {} + prefix_map_impl (std::initializer_list<value_type> init) + : prefix_map_common<M> (std::move (init), D) {} + }; + + template <typename M> + struct prefix_map_impl<M, 0>: prefix_map_common<M> + { + using prefix_map_common<M>::prefix_map_common; + }; + + template <typename K, + typename T, + typename compare_prefix<K>::char_type D = 0> + using prefix_map = prefix_map_impl<std::map<K, T, compare_prefix<K>>, D>; + + template <typename K, + typename T, + typename compare_prefix<K>::char_type D = 0> + using prefix_multimap = + prefix_map_impl<std::multimap<K, T, compare_prefix<K>>, D>; +} + +#include <build/prefix-map.txx> + +#endif // BUILD_PREFIX_MAP |