/*
* TokenPattern.cs
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 3
* of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307, USA.
*
* Copyright (c) 2003-2009 Per Cederberg. All rights reserved.
*/
using System;
using System.Text;
namespace PerCederberg.Grammatica.Runtime {
/**
* A token pattern. This class contains the definition of a token
* (i.e. it's pattern), and allows testing a string against this
* pattern. A token pattern is uniquely identified by an integer id,
* that must be provided upon creation.
*
* @author Per Cederberg, <per at percederberg dot net>
* @version 1.5
*/
public class TokenPattern {
/**
* The pattern type enumeration.
*/
public enum PatternType {
/**
* The string pattern type is used for tokens that only
* match an exact string.
*/
STRING,
/**
* The regular expression pattern type is used for tokens
* that match a regular expression.
*/
REGEXP
}
/**
* The token pattern identity.
*/
private int id;
/**
* The token pattern name.
*/
private string name;
/**
* The token pattern type.
*/
private PatternType type;
/**
* The token pattern.
*/
private string pattern;
/**
* The token error flag. If this flag is set, it means that an
* error should be reported if the token is found. The error
* message is present in the errorMessage variable.
*
* @see #errorMessage
*/
private bool error = false;
/**
* The token error message. This message will only be set if the
* token error flag is set.
*
* @see #error
*/
private string errorMessage = null;
/**
* The token ignore flag. If this flag is set, it means that the
* token should be ignored if found. If an ignore message is
* present in the ignoreMessage variable, it will also be reported
* as a warning.
*
* @see #ignoreMessage
*/
private bool ignore = false;
/**
* The token ignore message. If this message is set when the token
* ignore flag is also set, a warning message will be printed if
* the token is found.
*
* @see #ignore
*/
private string ignoreMessage = null;
/**
* The optional debug information message. This is normally set
* when the token pattern is analyzed by the tokenizer.
*/
private string debugInfo = null;
/**
* Creates a new token pattern.
*
* @param id the token pattern id
* @param name the token pattern name
* @param type the token pattern type
* @param pattern the token pattern
*/
public TokenPattern(int id,
string name,
PatternType type,
string pattern) {
this.id = id;
this.name = name;
this.type = type;
this.pattern = pattern;
}
/**
* The token pattern identity property (read-only). This
* property contains the unique token pattern identity value.
*
* @since 1.5
*/
public int Id {
get {
return id;
}
}
/**
* Returns the unique token pattern identity value.
*
* @return the token pattern id
*
* @see #Id
*
* @deprecated Use the Id property instead.
*/
public int GetId() {
return id;
}
/**
* The token pattern name property (read-only).
*
* @since 1.5
*/
public string Name {
get {
return name;
}
}
/**
* Returns the token pattern name.
*
* @return the token pattern name
*
* @see #Name
*
* @deprecated Use the Name property instead.
*/
public string GetName() {
return name;
}
/**
* The token pattern type property (read-only).
*
* @since 1.5
*/
public PatternType Type {
get {
return type;
}
}
/**
* Returns the token pattern type.
*
* @return the token pattern type
*
* @see #Type
*
* @deprecated Use the Type property instead.
*/
public PatternType GetPatternType() {
return type;
}
/**
* The token pattern property (read-only). This property
* contains the actual pattern (string or regexp) which have
* to be matched.
*
* @since 1.5
*/
public string Pattern {
get {
return pattern;
}
}
/**
* Returns te token pattern.
*
* @return the token pattern
*
* @see #Pattern
*
* @deprecated Use the Pattern property instead.
*/
public string GetPattern() {
return pattern;
}
/**
* The error flag property. If this property is true, the
* token pattern corresponds to an error token and an error
* should be reported if a match is found. When setting this
* property to true, a default error message is created if
* none was previously set.
*
* @since 1.5
*/
public bool Error {
get {
return error;
}
set {
error = value;
if (error && errorMessage == null) {
errorMessage = "unrecognized token found";
}
}
}
/**
* The token error message property. The error message is
* printed whenever the token is matched. Setting the error
* message property also sets the error flag to true.
*
* @see #Error
*
* @since 1.5
*/
public string ErrorMessage {
get {
return errorMessage;
}
set {
error = true;
errorMessage = value;
}
}
/**
* Checks if the pattern corresponds to an error token. If this
* is true, it means that an error should be reported if a
* matching token is found.
*
* @return true if the pattern maps to an error token, or
* false otherwise
*
* @see #Error
*
* @deprecated Use the Error property instead.
*/
public bool IsError() {
return Error;
}
/**
* Returns the token error message if the pattern corresponds to
* an error token.
*
* @return the token error message
*
* @see #ErrorMessage
*
* @deprecated Use the ErrorMessage property instead.
*/
public string GetErrorMessage() {
return ErrorMessage;
}
/**
* Sets the token error flag and assigns a default error message.
*
* @see #Error
*
* @deprecated Use the Error property instead.
*/
public void SetError() {
Error = true;
}
/**
* Sets the token error flag and assigns the specified error
* message.
*
* @param message the error message to display
*
* @see #ErrorMessage
*
* @deprecated Use the ErrorMessage property instead.
*/
public void SetError(string message) {
ErrorMessage = message;
}
/**
* The ignore flag property. If this property is true, the
* token pattern corresponds to an ignore token and should be
* skipped if a match is found.
*
* @since 1.5
*/
public bool Ignore {
get {
return ignore;
}
set {
ignore = value;
}
}
/**
* The token ignore message property. The ignore message is
* printed whenever the token is matched. Setting the ignore
* message property also sets the ignore flag to true.
*
* @see #Ignore
*
* @since 1.5
*/
public string IgnoreMessage {
get {
return ignoreMessage;
}
set {
ignore = true;
ignoreMessage = value;
}
}
/**
* Checks if the pattern corresponds to an ignored token. If this
* is true, it means that the token should be ignored if found.
*
* @return true if the pattern maps to an ignored token, or
* false otherwise
*
* @see #Ignore
*
* @deprecated Use the Ignore property instead.
*/
public bool IsIgnore() {
return Ignore;
}
/**
* Returns the token ignore message if the pattern corresponds to
* an ignored token.
*
* @return the token ignore message
*
* @see #IgnoreMessage
*
* @deprecated Use the IgnoreMessage property instead.
*/
public string GetIgnoreMessage() {
return IgnoreMessage;
}
/**
* Sets the token ignore flag and clears the ignore message.
*
* @see #Ignore
*
* @deprecated Use the Ignore property instead.
*/
public void SetIgnore() {
Ignore = true;
}
/**
* Sets the token ignore flag and assigns the specified ignore
* message.
*
* @param message the ignore message to display
*
* @see #IgnoreMessage
*
* @deprecated Use the IgnoreMessage property instead.
*/
public void SetIgnore(string message) {
IgnoreMessage = message;
}
/**
* The token debug info message property. This is normally be
* set when the token pattern is analyzed by the tokenizer.
*
* @since 1.5
*/
public string DebugInfo {
get {
return debugInfo;
}
set {
debugInfo = value;
}
}
/**
* Returns a string representation of this object.
*
* @return a token pattern string representation
*/
public override string ToString() {
StringBuilder buffer = new StringBuilder();
buffer.Append(name);
buffer.Append(" (");
buffer.Append(id);
buffer.Append("): ");
switch (type) {
case PatternType.STRING:
buffer.Append("\"");
buffer.Append(pattern);
buffer.Append("\"");
break;
case PatternType.REGEXP:
buffer.Append("<<");
buffer.Append(pattern);
buffer.Append(">>");
break;
}
if (error) {
buffer.Append(" ERROR: \"");
buffer.Append(errorMessage);
buffer.Append("\"");
}
if (ignore) {
buffer.Append(" IGNORE");
if (ignoreMessage != null) {
buffer.Append(": \"");
buffer.Append(ignoreMessage);
buffer.Append("\"");
}
}
if (debugInfo != null) {
buffer.Append("\n ");
buffer.Append(debugInfo);
}
return buffer.ToString();
}
/**
* Returns a short string representation of this object.
*
* @return a short string representation of this object
*/
public string ToShortString() {
StringBuilder buffer = new StringBuilder();
int newline = pattern.IndexOf('\n');
if (type == PatternType.STRING) {
buffer.Append("\"");
if (newline >= 0) {
if (newline > 0 && pattern[newline -1] == '\r') {
newline--;
}
buffer.Append(pattern.Substring(0, newline));
buffer.Append("(...)");
} else {
buffer.Append(pattern);
}
buffer.Append("\"");
} else {
buffer.Append("<");
buffer.Append(name);
buffer.Append(">");
}
return buffer.ToString();
}
}
}