aboutsummaryrefslogtreecommitdiff
path: root/src/include/open-axiom/InputFragment
blob: 65f3dfc980d2bd9df47e254b60fc488d8d4bcede (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
// -*- C++ -*-
// Copyright (C) 2014-2015, Gabriel Dos Reis.
// All rights reserved.
// Written by Gabriel Dos Reis.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     - Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//
//     - Redistributions in binary form must reproduce the above copyright
//       notice, this list of conditions and the following disclaimer in
//       the documentation and/or other materials provided with the
//       distribution.
//
//     - Neither the name of OpenAxiom. nor the names of its contributors
//       may be used to endorse or promote products derived from this
//       software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// --% Author: Gabriel Dos Reis

#ifndef OPENAXIOM_INPUTFRAGMENT_included
#define OPENAXIOM_INPUTFRAGMENT_included

#include <open-axiom/token>

namespace OpenAxiom {
   // A physical line is just raw text, coupled with location
   // information such as line and indentation column.
   struct Line : std::string {
      LineNumber number { };
      ColumnIndex indent { };
      
      std::string sub_string(ColumnIndex s, ColumnIndex e) const {
         return substr(s, e - s);
      }
   };

   // A program fragment is a logical line, composed of possibly
   // several physical lines subject to the off-side rule.  As a
   // special case, a line ending with the underbar character
   // continues to the next line with disregard to the off-side rule.
   struct Fragment : std::vector<Line> {
      explicit operator bool() const { return not empty(); }
      // Holds if the last physical line ends with line continuation marker.
      bool line_continuation() const {
         return not empty() and back().back() == '_';
      }
      // Return the indentation of the last physical line of this fragment.
      ColumnIndex last_indent() const {
         return empty() ? 0 : back().indent;
      }
      using std::vector<Line>::operator[];
      // Reference a line given by a position into this fragment.
      const Line& operator()(const OpenAxiom::FragmentCursor& pos) const {
         return (*this)[pos.line];
      }
      // Reference a character code unit at the position into this fragment.
      uint8_t operator[](const OpenAxiom::FragmentCursor& pos) const {
         return (*this)[pos.line][pos.column];
      }
      // Advance the cursor position to the next character code unit.
      uint8_t advance(OpenAxiom::FragmentCursor& pos) const {
         return (*this)[pos.line][pos.column++];
      }
      // This predicate holds if this fragment covers the cursor position.
      bool covering(const OpenAxiom::FragmentCursor& pos) const {
         return pos.column < (*this)[pos.line].size();
      }
   };

   std::ostream& operator<<(std::ostream&, const Fragment&);
}

#endif  // OPENAXIOM_INPUTFRAGMENT_included