sync/api/string_ordinal.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef SYNC_API_STRING_ORDINAL_H_
   6 #define SYNC_API_STRING_ORDINAL_H_
   7
   8 #include "base/basictypes.h"
   9 #include "sync/internal_api/public/base/ordinal.h"
  10
  11 namespace syncer {
  12
  13 // A StringOrdinal is an Ordinal with range 'a'-'z' for printability
  14 // of its internal byte string representation.  (Think of
  15 // StringOrdinal as being short for PrintableStringOrdinal.)  It
  16 // should be used for data types that want to maintain one or more
  17 // orderings for nodes.
  18 //
  19 // Since StringOrdinals contain only printable characters, it is safe
  20 // to store as a string in a protobuf.
  21
  22 struct StringOrdinalTraits {
  23   static const uint8 kZeroDigit = 'a';
  24   static const uint8 kMaxDigit = 'z';
  25   static const size_t kMinLength = 1;
  26 };
  27
  28 typedef Ordinal<StringOrdinalTraits> StringOrdinal;
  29
  30 COMPILE_ASSERT(StringOrdinal::kZeroDigit == 'a',
  31                StringOrdinalHasCorrectZeroDigit);
  32 COMPILE_ASSERT(StringOrdinal::kOneDigit == 'b',
  33                StringOrdinalHasCorrectOneDigit);
  34 COMPILE_ASSERT(StringOrdinal::kMidDigit == 'n',
  35                StringOrdinalHasCorrectMidDigit);
  36 COMPILE_ASSERT(StringOrdinal::kMaxDigit == 'z',
  37                StringOrdinalHasCorrectMaxDigit);
  38 COMPILE_ASSERT(StringOrdinal::kMidDigitValue == 13,
  39                StringOrdinalHasCorrectMidDigitValue);
  40 COMPILE_ASSERT(StringOrdinal::kMaxDigitValue == 25,
  41                StringOrdinalHasCorrectMaxDigitValue);
  42 COMPILE_ASSERT(StringOrdinal::kRadix == 26,
  43                StringOrdinalHasCorrectRadix);
  44
  45 }  // namespace syncer
  46
  47 #endif  // SYNC_API_STRING_ORDINAL_H_