diff options
Diffstat (limited to 'src/include')
| -rw-r--r-- | src/include/InputFragment.h | 90 | ||||
| -rw-r--r-- | src/include/token.H | 42 |
2 files changed, 114 insertions, 18 deletions
diff --git a/src/include/InputFragment.h b/src/include/InputFragment.h new file mode 100644 index 00000000..7f317973 --- /dev/null +++ b/src/include/InputFragment.h @@ -0,0 +1,90 @@ +// -*- C++ -*- +// Copyright (C) 2014, 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; + Line() : number(), 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 diff --git a/src/include/token.H b/src/include/token.H index 719f6e5f..71d6cb10 100644 --- a/src/include/token.H +++ b/src/include/token.H @@ -75,6 +75,10 @@ namespace OpenAxiom { std::ostream& operator<<(std::ostream&, TokenValue); + // Datatypes for locating lines and columns. + using LineNumber = std::size_t; + using ColumnIndex = std::size_t; + // Given a symbolic or alphabetic token, retrieve its category // and associated abstract value. struct TokenClassification { @@ -88,31 +92,33 @@ namespace OpenAxiom { TokenClassification classify(const std::string&); - // Datatypes for locating lines and columns. - using LineNumber = std::size_t; - using ColumnIndex = std::size_t; - // Cursor into a fragment. struct FragmentCursor { std::size_t line; // index of a line in a fragment std::size_t column; // column number at line. - }; - inline FragmentCursor& operator++(FragmentCursor& p) { - ++p.column; - return p; - } + inline FragmentCursor& operator++() { + ++column; + return *this; + } - inline FragmentCursor operator++(FragmentCursor& p, int) { - auto q = p; - ++p; - return q; - } + inline FragmentCursor operator++(int) { + auto tmp = *this; + ++*this; + return tmp; + } - inline FragmentCursor& operator--(FragmentCursor& p) { - --p.column; - return p; - } + inline FragmentCursor& operator--() { + --column; + return *this; + } + + inline FragmentCursor operator--(int) { + auto tmp = *this; + --*this; + return tmp; + } + }; // -- Exception types struct EndOfStringUnseen { |