implab/ImplabNet Files · Implab/Formats/InputScanner.cs

Rewritten JsonScanner, JsonParser, fixed naming style

cin - - Load All Authors

File last commit:

r228:6fa235c5a760 v2


                r228:6fa235c5a760

Download file

             InputScanner.cs
        
                    84 lines
            
             | 2.4 KiB
            
                | text/x-csharp
            
             |
                CSharpLexer
            
             / Implab / Formats / InputScanner.cs
          
                    History
                
                 |
                  Annotation
                 | Raw
                 |Copy content
                 |Copy permalink

      using Implab.Automaton;

      using System;

      using System.Collections.Generic;

      using System.Linq;

      using System.Text;

      using System.Threading.Tasks;

      namespace Implab.Formats {

          public class InputScanner<TTag> {

              readonly TTag[] m_tags;

              readonly int m_initialState;

              readonly int[,] m_dfa;

              readonly CharMap m_alphabet;

              readonly bool[] m_final;

              int m_position;

              int m_state;

              public InputScanner(int[,] dfaTable, bool[] finalStates, TTag[] tags, int initialState, CharMap alphabet) {

                  Safe.ArgumentNotNull(dfaTable, nameof(dfaTable));

                  Safe.ArgumentNotNull(finalStates, nameof(finalStates));

                  Safe.ArgumentNotNull(tags, nameof(tags));

                  Safe.ArgumentNotNull(alphabet, nameof(alphabet));

                  m_dfa = dfaTable;

                  m_final = finalStates;

                  m_tags = tags;

                  m_initialState = initialState;

                  m_alphabet = alphabet;

              }

              public TTag Tag {

                  get {

                      return m_tags[m_state];

                  }

              }

              public int Position {

                  get {

                      return m_position;

                  }

              }

              public bool IsFinal {

                  get {

                      return m_final[m_state];

                  }

              }

              public void Reset() {

                  m_state = m_initialState;

              }

              public InputScanner<TTag> Clone() {

                  var clone = new InputScanner<TTag>(m_dfa, m_final, m_tags, m_initialState, m_alphabet);

                  clone.m_state = m_state;

                  clone.m_position = m_position;

                  return clone;

              }

              public bool Scan(char[] data, int offset, int length) {

                  if (length <= 0) {

                      m_position = offset;

                      return false; // EOF

                  }

                  var max = offset + length;

                  var next = m_state;

                  while(offset < max) {

                      next = m_dfa[next, m_alphabet.Translate(data[offset])];

                      if (next == AutomatonConst.UNREACHABLE_STATE) {

                          // scanner stops on the next position after last recognized symbol

                          m_position = offset;

                          return false;

                      }

                      m_state = next;

                      offset++;

                  }

                  m_position = offset;

                  return true;

              }

          }

      }

	Site-wide shortcuts
/	Use quick search box
g h	Goto home page
g g	Goto my private gists page
g G	Goto my public gists page
g 0-9	Goto bookmarked items from 0-9
n r	New repository page
n g	New gist page

	Repositories
g s	Goto summary page
g c	Goto changelog page
g f	Goto files page
g F	Goto files page with file search activated
g p	Goto pull requests page
g o	Goto repository settings
g O	Goto repository access permissions settings
t s	Toggle sidebar on some pages

				using Implab.Automaton;
				using System;
				using System.Collections.Generic;
				using System.Linq;
				using System.Text;
				using System.Threading.Tasks;

				namespace Implab.Formats {
				public class InputScanner<TTag> {
				readonly TTag[] m_tags;
				readonly int m_initialState;
				readonly int[,] m_dfa;
				readonly CharMap m_alphabet;
				readonly bool[] m_final;

				int m_position;
				int m_state;

				public InputScanner(int[,] dfaTable, bool[] finalStates, TTag[] tags, int initialState, CharMap alphabet) {
				Safe.ArgumentNotNull(dfaTable, nameof(dfaTable));
				Safe.ArgumentNotNull(finalStates, nameof(finalStates));
				Safe.ArgumentNotNull(tags, nameof(tags));
				Safe.ArgumentNotNull(alphabet, nameof(alphabet));

				m_dfa = dfaTable;
				m_final = finalStates;
				m_tags = tags;
				m_initialState = initialState;
				m_alphabet = alphabet;
				}

				public TTag Tag {
				get {
				return m_tags[m_state];
				}
				}

				public int Position {
				get {
				return m_position;
				}
				}

				public bool IsFinal {
				get {
				return m_final[m_state];
				}
				}

				public void Reset() {
				m_state = m_initialState;
				}

				public InputScanner<TTag> Clone() {
				var clone = new InputScanner<TTag>(m_dfa, m_final, m_tags, m_initialState, m_alphabet);
				clone.m_state = m_state;
				clone.m_position = m_position;
				return clone;
				}

				public bool Scan(char[] data, int offset, int length) {
				if (length <= 0) {
				m_position = offset;
				return false; // EOF
				}

				var max = offset + length;
				var next = m_state;

				while(offset < max) {
				next = m_dfa[next, m_alphabet.Translate(data[offset])];
				if (next == AutomatonConst.UNREACHABLE_STATE) {
				// scanner stops on the next position after last recognized symbol
				m_position = offset;
				return false;
				}
				m_state = next;
				offset++;
				}
				m_position = offset;
				return true;
				}
				}
				}