internal static XbnfProduction Parse(ParseContext pc)
{
var result = new XbnfProduction();
pc.TrySkipCCommentsAndWhiteSpace();
// read identifier
result.Name = ParseIdentifier(pc);
// read attributes
if ('<' == pc.Current)
{
pc.Advance();
while (-1 != pc.Current && '>' != pc.Current)
{
result.Attributes.Add(XbnfAttribute.Parse(pc));
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting('>', ',');
if (',' == pc.Current)
{
pc.Advance();
}
}
pc.Expecting('>');
pc.Advance();
}
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting(';', '=');
if ('=' == pc.Current)
{
pc.Advance();
result.Expression = XbnfExpression.Parse(pc);
}
pc.Expecting(';');
pc.Advance();
return(result);
}
public void Advances()
{
var to = new ParseContext <Numbers>(Stock.Tokens.Stream(Numbers.Three, Numbers.Two, Numbers.One),
Numbers.EOF);
Assert.AreEqual(Numbers.Three, to.Current.Id);
Assert.IsTrue(to.Advance());
Assert.AreEqual(Numbers.Two, to.Current.Id);
Assert.IsTrue(to.Advance());
Assert.AreEqual(Numbers.One, to.Current.Id);
}
public void EofIsAtEndOfSource()
{
const string source = "OneTwoThree";
var to = new ParseContext <Numbers>(Stock.Lexers.GetOneTwoThree().Tokenize(source),
Numbers.EOF);
to.Advance(); // Two
to.Advance(); // Three
to.Advance(); // EOF
Assert.AreEqual(Numbers.EOF, to.Current.Id);
Assert.AreEqual(source.Length, to.Current.Start);
Assert.AreEqual(0, to.Current.Length);
}
public void AdancedPastEndBecomesEOF()
{
var to = new ParseContext <Numbers>(Stock.Tokens.Stream(Numbers.One).ToList(),
Numbers.EOF);
Assert.IsFalse(to.Advance());
Assert.AreEqual(Numbers.EOF, to.Current.Id);
}
static void _ParseAttributes(EbnfDocument doc, string id, EbnfProduction prod, ParseContext pc)
{
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting('<');
pc.Advance();
while (-1 != pc.Current && '>' != pc.Current)
{
_ParseAttribute(doc, id, prod, pc);
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting(',', '>');
if (',' == pc.Current)
{
pc.Advance();
}
}
pc.Expecting('>');
pc.Advance();
pc.TrySkipCCommentsAndWhiteSpace();
}
static void _ParseProduction(EbnfDocument doc, ParseContext pc)
{
pc.TrySkipCCommentsAndWhiteSpace();
var line = pc.Line;
var column = pc.Column;
var position = pc.Position;
var id = _ParseIdentifier(pc);
pc.TrySkipCCommentsAndWhiteSpace();
EbnfProduction prod = null;
if (!doc.Productions.TryGetValue(id, out prod))
{
prod = new EbnfProduction();
doc.Productions.Add(id, prod);
}
if ('<' == pc.Current)
{
_ParseAttributes(doc, id, prod, pc);
pc.TrySkipCCommentsAndWhiteSpace();
}
pc.Expecting('=');
pc.Advance();
pc.Expecting();
var expr = _ParseExpression(doc, pc);
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting(';');
pc.Advance();
pc.TrySkipCCommentsAndWhiteSpace();
// transform this into an OrExpression with the previous
if (null != prod.Expression)
{
prod.Expression = new EbnfOrExpression(prod.Expression, expr);
}
else
{
prod.Expression = expr;
}
prod.SetLocationInfo(line, column, position);
}
static RegexExpression _ParseModifier(RegexExpression expr, ParseContext pc)
{
var line = pc.Line;
var column = pc.Column;
var position = pc.Position;
switch (pc.Current)
{
case '*':
expr = new RegexRepeatExpression(expr);
expr.SetLocation(line, column, position);
pc.Advance();
break;
case '+':
expr = new RegexRepeatExpression(expr, 1);
expr.SetLocation(line, column, position);
pc.Advance();
break;
case '?':
expr = new RegexOptionalExpression(expr);
expr.SetLocation(line, column, position);
pc.Advance();
break;
case '{':
pc.Advance();
pc.TrySkipWhiteSpace();
pc.Expecting('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ',', '}');
var min = -1;
var max = -1;
if (',' != pc.Current && '}' != pc.Current)
{
var l = pc.CaptureBuffer.Length;
pc.TryReadDigits();
min = int.Parse(pc.GetCapture(l));
pc.TrySkipWhiteSpace();
}
if (',' == pc.Current)
{
pc.Advance();
pc.TrySkipWhiteSpace();
pc.Expecting('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '}');
if ('}' != pc.Current)
{
var l = pc.CaptureBuffer.Length;
pc.TryReadDigits();
max = int.Parse(pc.GetCapture(l));
pc.TrySkipWhiteSpace();
}
}
pc.Expecting('}');
pc.Advance();
expr = new RegexRepeatExpression(expr, min, max);
expr.SetLocation(line, column, position);
break;
}
return(expr);
}
static bool _DoMatchDfa(CharDfaEntry[] dfaTable, ParseContext context)
{
// track our current state
var state = 0;
// prepare the parse context
context.EnsureStarted();
while (true)
{
// if no more input
if (-1 == context.Current)
{
// if we accept, return that
return(-1 != dfaTable[state].AcceptSymbolId);
}
// move by current character
var newState = MoveDfa(dfaTable, state, (char)context.Current);
// we couldn't match anything
if (-1 == newState)
{
// if we accept, return that
if (-1 != dfaTable[state].AcceptSymbolId)
{
return(true);
}
// otherwise error
// advance the input
context.Advance();
return(false);
}
// store the current character
context.CaptureCurrent();
// advance the input
context.Advance();
// iterate to our next states
state = newState;
}
}
static bool _SkipWhiteSpace(ParseContext pc)
{
pc.EnsureStarted();
if (-1 == pc.Current || '\n' == pc.Current || !char.IsWhiteSpace((char)pc.Current))
{
return(false);
}
while (-1 != pc.Advance() && '\n' != pc.Current && char.IsWhiteSpace((char)pc.Current))
{
;
}
return(true);
}
static CfgRule _Parse(ParseContext pc)
{
var result = new CfgRule();
pc.TrySkipWhiteSpace();
pc.ClearCapture();
pc.TryReadUntil(false, ' ', '\t', '\r', '\n', '\f', '\v', '-');
result.Left = pc.Capture;
pc.TrySkipWhiteSpace();
pc.Expecting('-');
pc.Advance();
pc.Expecting('>');
pc.Advance();
while (-1 != pc.Current && '\n' != pc.Current)
{
pc.TrySkipWhiteSpace();
pc.ClearCapture();
pc.TryReadUntil(false, ' ', '\t', '\r', '\n', '\f', '\v');
result.Right.Add(pc.Capture);
}
return(result);
}
bool _DoMatchDfa(ParseContext context)
{
// track the current state
var state = this;
while (true)
{
// if no more input
if (-1 == context.Current)
{
// if we accept, return that
return(state.IsAccepting);
}
// move by current character
var newState = state.MoveDfa((char)context.Current);
// we couldn't match anything
if (null == newState)
{
// if we accept, return that
if (state.IsAccepting)
{
return(true);
}
// otherwise error
// advance the input
context.Advance();
return(false);
}
// store the current character
context.CaptureCurrent();
// advance the input
context.Advance();
// iterate to our next state
state = newState;
}
}
// almost the same as our lex methods
bool _DoMatch(ParseContext context)
{
// get the initial states
var states = FillEpsilonClosure();
while (true)
{
// if no more input
if (-1 == context.Current)
{
// if we accept, return that
return(IsAnyAccepting(states));
}
// move by current character
var newStates = FillMove(states, (char)context.Current);
// we couldn't match anything
if (0 == newStates.Count)
{
// if we accept, return that
if (IsAnyAccepting(states))
{
return(true);
}
// otherwise error
// advance the input
context.Advance();
return(false);
}
// store the current character
context.CaptureCurrent();
// advance the input
context.Advance();
// iterate to our next states
states = newStates;
}
}
static void _ParseAttribute(EbnfDocument doc, string id, EbnfProduction prod, ParseContext pc)
{
pc.TrySkipCCommentsAndWhiteSpace();
var attrid = _ParseIdentifier(pc);
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting('=', '>', ',');
object val = true;
if ('=' == pc.Current)
{
pc.Advance();
val = pc.ParseJsonValue();
}
pc.Expecting(',', '>');
prod.Attributes[attrid] = val;
pc.TrySkipCCommentsAndWhiteSpace();
}
public void AdanceWellBeyondEnd()
{
var to = new ParseContext <Numbers>(Stock.Tokens.Stream(Numbers.One),
Numbers.EOF);
Assert.IsFalse(to.Advance());
Assert.IsFalse(to.Advance());
Assert.IsFalse(to.Advance());
Assert.IsFalse(to.Advance());
Assert.IsFalse(to.Advance());
Assert.IsFalse(to.Advance());
Assert.AreEqual(Numbers.EOF, to.Current.Id);
}
internal static XbnfAttribute Parse(ParseContext pc)
{
pc.TrySkipCCommentsAndWhiteSpace();
var attr = new XbnfAttribute();
attr.SetLocation(pc.Line, pc.Column, pc.Position);
attr.Name = ParseIdentifier(pc);
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting(',', '=', ',', '>');
if ('=' == pc.Current)
{
pc.Advance();
attr.Value = pc.ParseJsonValue();
}
else
{
attr.Value = true;
}
return(attr);
}
internal static LexAttribute Parse(ParseContext pc)
{
SkipCommentsAndWhitespace(pc);
var attr = new LexAttribute();
attr.SetLocation(pc.Line, pc.Column, pc.Position);
attr.Name = _ParseAttrName(pc);
SkipCommentsAndWhitespace(pc);
pc.Expecting(',', '=', ',', '>', '\n');
if ('=' == pc.Current)
{
pc.Advance();
attr.Value = pc.ParseJsonValue();
}
else
{
attr.Value = true;
}
return(attr);
}
static string _ParseIdentifier(ParseContext pc)
{
pc.TrySkipCCommentsAndWhiteSpace();
if (-1 == pc.Current)
{
pc.Expecting();
return(null);
}
var l = pc.CaptureBuffer.Length;
if ('_' != pc.Current && !char.IsLetter((char)pc.Current))
{
pc.Expecting("ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz".ToCharArray().Convert <int>().ToArray());
}
pc.CaptureCurrent();
while (-1 != pc.Advance() && ('_' == pc.Current || '-' == pc.Current || char.IsLetterOrDigit((char)pc.Current)))
{
pc.CaptureCurrent();
}
pc.TrySkipCCommentsAndWhiteSpace();
return(pc.GetCapture(l));
}
protected bool ParseDateTime(string s, DateTimePart part)
{
ParseContext context = new ParseContext(s);
bool bDatePart = ( part & DateTimePart.Date ) != 0;
bool bTimePart = ( part & DateTimePart.Time ) != 0;
int year = 0, month = 0, day = 0;
int hour = 0, minute = 0;
double second = 0;
eTZ = ETZ.Missing;
offsetTZ = 0;
if ( bDatePart )
{
// parse date
bool bNegative = context.CheckAndAdvance( '-' );
if ( (part & DateTimePart.Year ) != 0 )
{
int digits = 0;
int temp = 0;
while ( context.ReadDigitAndAdvance( ref temp, 1, 9 ) )
{
year = year * 10 + temp;
digits += 1;
temp = 0;
if (digits >= 8) // overflow
return false;
}
if ( digits < 4 ) // invalid.
return false;
if ( digits > 4 && year < 10000 )
return false;
if (bNegative)
year = -year;
}
if ( (part & ( DateTimePart.Month | DateTimePart.Day )) != 0 )
{
if ( !context.CheckAndAdvance( '-' ) ) return false;
if ( ( part & DateTimePart.Month ) != 0 )
{
if ( !context.ReadDigitAndAdvance( ref month, 10, 1 ) ) return false;
if ( !context.ReadDigitAndAdvance( ref month, 1, month < 10 ? 9 : 2 ) ) return false;
if ( month == 0 ) return false;
}
if ( ( part & DateTimePart.Day ) != 0 )
{
if ( !context.CheckAndAdvance( '-') ) return false;
int maxFirstDigit = month != 2 ? 3 : 2;
// complicate things by making them complicated.
if ( !context.ReadDigitAndAdvance( ref day, 10, maxFirstDigit ) ) return false;
if ( !context.ReadDigitAndAdvance( ref day, 1, 9 ) ) return false;
if ( day == 0 || day > 31 ) return false;
if ( ( part & DateTimePart.Month ) != 0 )
{
bool b1 = month <= 7;
bool b2 = ( month & 1 ) == 0;
// month 1, 3, 5, 7, 8, 10, 12
if ( b1 == b2 && day > 30 )
return false;
// february.
if ( month == 2 && day > 29 )
return false;
// leap years.
if ( month == 2 && ( part & DateTimePart.Year ) != 0 &&
( year % 4 != 0 || year % 100 == 0 ) && year % 400 != 0 &&
day > 28 )
return false;
}
}
}
if ( bTimePart )
{
// a 'T' must follow
if ( !context.CheckAndAdvance( 'T') ) return false;
}
}
if ( bTimePart )
{
// check format here
// hour from 0 to 2
if ( !context.ReadDigitAndAdvance( ref hour, 10, 2 ) ) return false;
if ( !context.ReadDigitAndAdvance( ref hour, 1, hour < 20 ? 9 : 4 ) ) return false;
if ( !context.CheckAndAdvance( ':' ) ) return false;
int maxFirstDigit = hour == 24 ? 0 : 5;
int maxSecondDigit = hour == 24 ? 0 : 9;
if ( !context.ReadDigitAndAdvance( ref minute, 10, maxFirstDigit ) ) return false;
if ( !context.ReadDigitAndAdvance( ref minute, 1, maxSecondDigit ) ) return false;
if ( !context.CheckAndAdvance( ':' ) ) return false;
int secondInt = 0;
if ( !context.ReadDigitAndAdvance( ref secondInt, 10, maxFirstDigit ) ) return false;
if ( !context.ReadDigitAndAdvance( ref secondInt, 1, maxSecondDigit ) ) return false;
second = secondInt;
if ( context.CheckAndAdvance( '.' ) )
{
// fraction. do whatever seems fit.
int val = 0;
int digits = 0;
while ( context.ReadDigitAndAdvance( ref val, 1, 9) )
{
val *= 10;
digits += 1;
if ( digits >= 8 ) // precision loss - ignore
break;
}
if ( digits == 0 )
return false;
second += val * Math.Pow( 10.0, -digits - 1 );
// skip any further digits.
while ( context.ReadDigitAndAdvance( ref val, 0, 9) )
;
}
}
// timezone
if ( context.CheckAndAdvance('Z') )
{
// timezone specified, it is UTC.
eTZ = ETZ.UTC;
offsetTZ = 0;
}
else if ( context.Check('+') || context.Check('-' ) )
{
// timezone offset, in hour:minute format
bool bNegative = context.Check('-');
context.Advance();
// do not check the hour part, for those who are obscure.
int temp = 0;
if ( !context.ReadDigitAndAdvance( ref temp, 600, 9 ) ) return false;
if ( !context.ReadDigitAndAdvance( ref temp, 60, 9 ) ) return false;
if ( !context.CheckAndAdvance( ':' ) ) return false;
if ( !context.ReadDigitAndAdvance( ref temp, 10, 5 ) ) return false;
if ( !context.ReadDigitAndAdvance( ref temp, 1, 9 ) ) return false;
eTZ = ETZ.Offset;
offsetTZ = bNegative ? -temp : temp;
}
if ( context.IsValid() )
return false;
// C# specific
if (year <= 0) year = 1;
if (month == 0) month = 1;
bool badjust = false;
if (hour == 24)
{
hour = 0;
badjust = true;
}
if (day == 0) day = 1;
try {
myValue = new System.DateTime(year, month, day, hour, minute, (int)second,
(int)(second * 1000) % 1000);
if (badjust)
myValue.AddDays(1);
}
catch
{
return false;
}
return true;
}
bool ParseDateTime(string s, DateTimePart part)
{
ParseContext context = new ParseContext(s);
bool bDatePart = (part & DateTimePart.Date) != 0;
bool bTimePart = (part & DateTimePart.Time) != 0;
int year = 0, month = 0, day = 0;
int hour = 0, minute = 0;
double second = 0;
timezone = NoTimezone;
if (bDatePart)
{
// parse date
bool bNegative = context.CheckAndAdvance('-');
if ((part & DateTimePart.Year) != 0)
{
int digits = 0;
int temp = 0;
while (context.ReadDigitAndAdvance(ref temp, 1, 9))
{
year = year * 10 + temp;
digits += 1;
temp = 0;
if (digits >= 8) // overflow
{
return(false);
}
}
if (digits < 4) // invalid.
{
return(false);
}
if (digits > 4 && year < 10000)
{
return(false);
}
if (bNegative)
{
year = -year;
}
}
if ((part & (DateTimePart.Month | DateTimePart.Day)) != 0)
{
if (!context.CheckAndAdvance('-'))
{
return(false);
}
if ((part & DateTimePart.Month) != 0)
{
if (!context.ReadDigitAndAdvance(ref month, 10, 1))
{
return(false);
}
if (!context.ReadDigitAndAdvance(ref month, 1, month < 10 ? 9 : 2))
{
return(false);
}
if (month == 0)
{
return(false);
}
}
if ((part & DateTimePart.Day) != 0)
{
if (!context.CheckAndAdvance('-'))
{
return(false);
}
int maxFirstDigit = month != 2 ? 3 : 2;
// complicate things by making them complicated.
if (!context.ReadDigitAndAdvance(ref day, 10, maxFirstDigit))
{
return(false);
}
if (!context.ReadDigitAndAdvance(ref day, 1, 9))
{
return(false);
}
if (day == 0 || day > 31)
{
return(false);
}
if ((part & DateTimePart.Month) != 0)
{
bool b1 = month <= 7;
bool b2 = (month & 1) == 0;
// month 1, 3, 5, 7, 8, 10, 12
if (b1 == b2 && day > 30)
{
return(false);
}
// february.
if (month == 2 && day > 29)
{
return(false);
}
// leap years.
if (month == 2 && (part & DateTimePart.Year) != 0 &&
(year % 4 != 0 || year % 100 == 0) && year % 400 != 0 &&
day > 28)
{
return(false);
}
}
}
}
if (bTimePart)
{
// a 'T' must follow
if (!context.CheckAndAdvance('T'))
{
return(false);
}
}
}
if (bTimePart)
{
// check format here
// hour from 0 to 2
if (!context.ReadDigitAndAdvance(ref hour, 10, 2))
{
return(false);
}
if (!context.ReadDigitAndAdvance(ref hour, 1, hour < 20 ? 9 : 4))
{
return(false);
}
if (!context.CheckAndAdvance(':'))
{
return(false);
}
int maxFirstDigit = hour == 24 ? 0 : 5;
int maxSecondDigit = hour == 24 ? 0 : 9;
if (!context.ReadDigitAndAdvance(ref minute, 10, maxFirstDigit))
{
return(false);
}
if (!context.ReadDigitAndAdvance(ref minute, 1, maxSecondDigit))
{
return(false);
}
if (!context.CheckAndAdvance(':'))
{
return(false);
}
int secondInt = 0;
if (!context.ReadDigitAndAdvance(ref secondInt, 10, maxFirstDigit))
{
return(false);
}
if (!context.ReadDigitAndAdvance(ref secondInt, 1, maxSecondDigit))
{
return(false);
}
second = secondInt;
if (context.CheckAndAdvance('.'))
{
// fraction. do whatever seems fit.
int val = 0;
int digits = 0;
while (context.ReadDigitAndAdvance(ref val, 1, 9))
{
val *= 10;
digits += 1;
if (digits >= 8) // precision loss - ignore
{
break;
}
}
if (digits == 0)
{
return(false);
}
second += val * System.Math.Pow(10.0, -digits - 1);
// skip any further digits.
while (context.ReadDigitAndAdvance(ref val, 0, 9))
{
;
}
}
}
// timezone
if (context.CheckAndAdvance('Z'))
{
// timezone specified, it is UTC.
timezone = 0;
}
else if (context.Check('+') || context.Check('-'))
{
// timezone offset, in hour:minute format
bool bNegative = context.Check('-');
context.Advance();
// do not check the hour part, for those who are obscure.
int temp = 0;
if (!context.ReadDigitAndAdvance(ref temp, 600, 9))
{
return(false);
}
if (!context.ReadDigitAndAdvance(ref temp, 60, 9))
{
return(false);
}
if (!context.CheckAndAdvance(':'))
{
return(false);
}
if (!context.ReadDigitAndAdvance(ref temp, 10, 5))
{
return(false);
}
if (!context.ReadDigitAndAdvance(ref temp, 1, 9))
{
return(false);
}
timezone = (short)(bNegative ? -temp : temp);
}
if (context.IsValid())
{
return(false);
}
// C# specific
if (year <= 0)
{
year = 1;
}
if (month == 0)
{
month = 1;
}
bool badjust = false;
if (hour == 24)
{
hour = 0;
badjust = true;
}
if (day == 0)
{
day = 1;
}
if ((part & DateTimePart.Year) == 0 && month == 2 && day == 29)
{
year = 4;
}
try
{
myValue = new System.DateTime(year, month, day, hour, minute, (int)second,
(int)(second * 1000) % 1000);
if (badjust)
{
myValue.AddDays(1);
}
}
catch
{
return(false);
}
return(true);
}
internal static RegexExpression Parse(ParseContext pc)
{
RegexExpression result = null, next = null;
int ich;
pc.EnsureStarted();
var line = pc.Line;
var column = pc.Column;
var position = pc.Position;
while (true)
{
switch (pc.Current)
{
case -1:
return(result);
case '.':
var nset = new RegexCharsetExpression(new RegexCharsetEntry[] { new RegexCharsetRangeEntry(char.MinValue, char.MaxValue) }, false);
nset.SetLocation(line, column, position);
if (null == result)
{
result = nset;
}
else
{
result = new RegexConcatExpression(result, nset);
result.SetLocation(line, column, position);
}
pc.Advance();
result = _ParseModifier(result, pc);
line = pc.Line;
column = pc.Column;
position = pc.Position;
break;
case '\\':
if (-1 != (ich = _ParseEscape(pc)))
{
next = new RegexLiteralExpression((char)ich);
next.SetLocation(line, column, position);
next = _ParseModifier(next, pc);
if (null != result)
{
result = new RegexConcatExpression(result, next);
result.SetLocation(line, column, position);
}
else
{
result = next;
}
}
else
{
pc.Expecting(); // throw an error
return(null); // doesn't execute
}
line = pc.Line;
column = pc.Column;
position = pc.Position;
break;
case ')':
return(result);
case '(':
pc.Advance();
pc.Expecting();
next = Parse(pc);
pc.Expecting(')');
pc.Advance();
next = _ParseModifier(next, pc);
if (null == result)
{
result = next;
}
else
{
result = new RegexConcatExpression(result, next);
result.SetLocation(line, column, position);
}
line = pc.Line;
column = pc.Column;
position = pc.Position;
break;
case '|':
if (-1 != pc.Advance())
{
next = Parse(pc);
result = new RegexOrExpression(result, next);
result.SetLocation(line, column, position);
}
else
{
result = new RegexOrExpression(result, null);
result.SetLocation(line, column, position);
}
line = pc.Line;
column = pc.Column;
position = pc.Position;
break;
case '[':
pc.ClearCapture();
pc.Advance();
pc.Expecting();
bool not = false;
if ('^' == pc.Current)
{
not = true;
pc.Advance();
pc.Expecting();
}
var ranges = _ParseRanges(pc);
if (ranges.Count == 0)
{
System.Diagnostics.Debugger.Break();
}
pc.Expecting(']');
pc.Advance();
next = new RegexCharsetExpression(ranges, not);
next.SetLocation(line, column, position);
next = _ParseModifier(next, pc);
if (null == result)
{
result = next;
}
else
{
result = new RegexConcatExpression(result, next);
result.SetLocation(pc.Line, pc.Column, pc.Position);
}
line = pc.Line;
column = pc.Column;
position = pc.Position;
break;
default:
ich = pc.Current;
next = new RegexLiteralExpression((char)ich);
next.SetLocation(line, column, position);
pc.Advance();
next = _ParseModifier(next, pc);
if (null == result)
{
result = next;
}
else
{
result = new RegexConcatExpression(result, next);
result.SetLocation(line, column, position);
}
line = pc.Line;
column = pc.Column;
position = pc.Position;
break;
}
}
}
/// <summary>
/// Converts a string containing set of values separated by commas into
/// a <see cref="Data"/> object for interaction with individual values
/// </summary>
/// <param name="csvContent"></param>
/// <param name="options"></param>
/// <returns></returns>
public static Data Parse(string csvContent, ParseOptions options = null)
{
var context = new ParseContext <Tokens>(Lexer.Default.Tokenize(csvContent), Tokens.EOF);
var r = new Data();
var addHeader = options?.HasHeaders ?? true;
List <string> headers = null;
var items = new List <string>();
while (context.Current.Id != Tokens.EOF)
{
switch (context.Current.Id)
{
case Tokens.Value:
items.Add(context.Current.Value);
break;
case Tokens.EOL:
if (addHeader)
{
headers = items;
}
else
{
r.AddRow(items);
}
addHeader = false;
items = new List <string>();
break;
// TODO: Add error handling and report these token types as errors
//case Tokens.Unknown:
// break;
//case Tokens.Unterminated:
// break;
// There is nothing to be done with these token types
//case Tokens.EOF:
// break;
//case Tokens.Delimiter:
// break;
//case Tokens.NullValue:
// break;
//case Tokens.Quoted:
// break;
//case Tokens.EmbeddedQuoted:
// break;
}
context.Advance();
}
if (items.Any())
{
r.AddRow(items);
}
r.SetHeaders(headers?.Any() == true ? headers : Enumerable.Range(0, items.Count).Select(i => $"Column {i}").ToList());
return(r);
}
static EbnfExpression _ParseExpression(EbnfDocument doc, ParseContext pc)
{
EbnfExpression current = null;
EbnfExpression e;
long position;
int line;
int column;
pc.TrySkipCCommentsAndWhiteSpace();
position = pc.Position; line = pc.Line; column = pc.Column;
while (-1 != pc.Current && ']' != pc.Current && ')' != pc.Current && '}' != pc.Current && ';' != pc.Current)
{
pc.TrySkipCCommentsAndWhiteSpace();
position = pc.Position; line = pc.Line; column = pc.Column;
switch (pc.Current)
{
case '|':
pc.Advance();
current = new EbnfOrExpression(current, _ParseExpression(doc, pc));
current.SetLocationInfo(line, column, position);
break;
case '(':
pc.Advance();
e = _ParseExpression(doc, pc);
current.SetLocationInfo(line, column, position);
pc.Expecting(')');
pc.Advance();
e.SetLocationInfo(line, column, position);
if (null == current)
{
current = e;
}
else
{
current = new EbnfConcatExpression(current, e);
}
break;
case '[':
pc.Advance();
e = new EbnfOptionalExpression(_ParseExpression(doc, pc));
e.SetLocationInfo(line, column, position);
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting(']');
pc.Advance();
if (null == current)
{
current = e;
}
else
{
current = new EbnfConcatExpression(current, e);
}
break;
case '{':
pc.Advance();
e = new EbnfRepeatExpression(_ParseExpression(doc, pc));
e.SetLocationInfo(line, column, position);
pc.TrySkipCCommentsAndWhiteSpace();
pc.Expecting('}');
pc.Advance();
if ('+' == pc.Current)
{
pc.Advance();
((EbnfRepeatExpression)e).IsOptional = false;
}
if (null == current)
{
current = e;
}
else
{
current = new EbnfConcatExpression(current, e);
}
break;
case '\"':
e = new EbnfLiteralExpression(pc.ParseJsonString());
if (null == current)
{
current = e;
}
else
{
current = new EbnfConcatExpression(current, e);
}
e.SetLocationInfo(line, column, position);
break;
case '\'':
pc.Advance();
pc.ClearCapture();
pc.TryReadUntil('\'', '\\', false);
pc.Expecting('\'');
pc.Advance();
e = new EbnfRegexExpression(pc.Capture);
if (null == current)
{
current = e;
}
else
{
current = new EbnfConcatExpression(current, e);
}
e.SetLocationInfo(line, column, position);
break;
case ';':
case ']':
case ')':
case '}':
return(current);
default:
e = new EbnfRefExpression(_ParseIdentifier(pc));
if (null == current)
{
current = e;
}
else
{
current = new EbnfConcatExpression(current, e);
}
e.SetLocationInfo(line, column, position);
break;
}
}
pc.TrySkipCCommentsAndWhiteSpace();
return(current);
}
static int _ParseEscape(ParseContext pc)
{
if ('\\' != pc.Current)
{
return(-1);
}
if (-1 == pc.Advance())
{
return(-1);
}
switch (pc.Current)
{
case 't':
pc.Advance();
return('\t');
case 'n':
pc.Advance();
return('\n');
case 'r':
pc.Advance();
return('\r');
case 'x':
if (-1 == pc.Advance())
{
return('x');
}
byte b = _FromHexChar((char)pc.Current);
b <<= 4;
if (-1 == pc.Advance())
{
return(unchecked ((char)b));
}
b |= _FromHexChar((char)pc.Current);
return(unchecked ((char)b));
case 'u':
if (-1 == pc.Advance())
{
return('u');
}
ushort u = _FromHexChar((char)pc.Current);
u <<= 4;
if (-1 == pc.Advance())
{
return(unchecked ((char)u));
}
u |= _FromHexChar((char)pc.Current);
u <<= 4;
if (-1 == pc.Advance())
{
return(unchecked ((char)u));
}
u |= _FromHexChar((char)pc.Current);
u <<= 4;
if (-1 == pc.Advance())
{
return(unchecked ((char)u));
}
u |= _FromHexChar((char)pc.Current);
return(unchecked ((char)u));
default:
int i = pc.Current;
pc.Advance();
return((char)i);
}
}
static IList <RegexCharsetEntry> _ParseRanges(ParseContext pc)
{
pc.EnsureStarted();
var result = new List <RegexCharsetEntry>();
RegexCharsetEntry next = null;
bool readDash = false;
while (-1 != pc.Current && ']' != pc.Current)
{
switch (pc.Current)
{
case '[': // char class
if (null != next)
{
result.Add(next);
if (readDash)
{
result.Add(new RegexCharsetCharEntry('-'));
}
result.Add(new RegexCharsetCharEntry('-'));
}
pc.Advance();
pc.Expecting(':');
pc.Advance();
var l = pc.CaptureBuffer.Length;
pc.TryReadUntil(':', false);
var n = pc.GetCapture(l);
pc.Advance();
pc.Expecting(']');
pc.Advance();
result.Add(new RegexCharsetClassEntry(n));
readDash = false;
next = null;
break;
case '\\':
//pc.Advance();
//pc.Expecting();
var ch = (char)_ParseEscape(pc);
if (null == next)
{
next = new RegexCharsetCharEntry(ch);
}
else
{
if (readDash)
{
result.Add(new RegexCharsetRangeEntry(((RegexCharsetCharEntry)next).Value, ch));
next = null;
readDash = false;
}
else
{
result.Add(next);
next = new RegexCharsetCharEntry(ch);
}
}
break;
case '-':
pc.Advance();
if (null == next)
{
next = new RegexCharsetCharEntry('-');
readDash = false;
}
else
{
if (readDash)
{
result.Add(next);
}
readDash = true;
}
break;
default:
if (null == next)
{
next = new RegexCharsetCharEntry((char)pc.Current);
}
else
{
if (readDash)
{
result.Add(new RegexCharsetRangeEntry(((RegexCharsetCharEntry)next).Value, (char)pc.Current));
next = null;
readDash = false;
}
else
{
result.Add(next);
next = new RegexCharsetCharEntry((char)pc.Current);
}
}
pc.Advance();
break;
}
}
if (null != next)
{
result.Add(next);
if (readDash)
{
next = new RegexCharsetCharEntry('-');
result.Add(next);
}
}
return(result);
}
static CharFA <TAccept> _Parse(ParseContext pc, TAccept accept)
{
CharFA <TAccept> result = new CharFA <TAccept>(true, accept);
CharFA <TAccept> f, next;
int ch;
pc.EnsureStarted();
var current = result;
while (true)
{
switch (pc.Current)
{
case -1:
return(result);
case '.':
pc.Advance();
f = current.FirstAcceptingState as CharFA <TAccept>;
current = Set(new CharRange[] { new CharRange(char.MinValue, char.MaxValue) }, accept);
switch (pc.Current)
{
case '*':
current = Kleene(current, accept);
pc.Advance();
break;
case '+':
current = Repeat(current, accept);
pc.Advance();
break;
case '?':
current = Optional(current, accept);
pc.Advance();
break;
}
f.IsAccepting = false;
f.EpsilonTransitions.Add(current);
break;
case '\\':
if (-1 != (ch = _ParseEscape(pc)))
{
next = null;
switch (pc.Current)
{
case '*':
next = new CharFA <TAccept>();
next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
next = Kleene(next, accept);
pc.Advance();
break;
case '+':
next = new CharFA <TAccept>();
next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
next = Repeat(next, accept);
pc.Advance();
break;
case '?':
next = new CharFA <TAccept>();
next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
next = Optional(next, accept);
pc.Advance();
break;
default:
current = current.FirstAcceptingState as CharFA <TAccept>;
current.IsAccepting = false;
current.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
break;
}
if (null != next)
{
current = current.FirstAcceptingState as CharFA <TAccept>;
current.IsAccepting = false;
current.EpsilonTransitions.Add(next);
current = next;
}
}
else
{
pc.Expecting(); // throw an error
return(null); // doesn't execute
}
break;
case ')':
return(result);
case '(':
pc.Advance();
pc.Expecting();
f = current.FirstAcceptingState as CharFA <TAccept>;
current = _Parse(pc, accept);
pc.Expecting(')');
pc.Advance();
switch (pc.Current)
{
case '*':
current = Kleene(current, accept);
pc.Advance();
break;
case '+':
current = Repeat(current, accept);
pc.Advance();
break;
case '?':
current = Optional(current, accept);
pc.Advance();
break;
}
var ff = f.FirstAcceptingState;
ff.EpsilonTransitions.Add(current);
ff.IsAccepting = false;
break;
case '|':
if (-1 != pc.Advance())
{
current = _Parse(pc, accept);
result = Or(new CharFA <TAccept>[] { result as CharFA <TAccept>, current as CharFA <TAccept> }, accept);
}
else
{
current = current.FirstAcceptingState as CharFA <TAccept>;
result = Optional(result, accept);
}
break;
case '[':
pc.ClearCapture();
pc.Advance();
pc.Expecting();
bool not = false;
if ('^' == pc.Current)
{
not = true;
pc.Advance();
pc.Expecting();
}
pc.TryReadUntil(']', '\\', false);
pc.Expecting(']');
pc.Advance();
var r = (!not && "." == pc.Capture) ?
new CharRange[] { new CharRange(char.MinValue, char.MaxValue) } :
_ParseRanges(pc.Capture, true);
if (not)
{
r = CharRange.NotRanges(r);
}
f = current.FirstAcceptingState as CharFA <TAccept>;
current = Set(r, accept);
switch (pc.Current)
{
case '*':
current = Kleene(current, accept);
pc.Advance();
break;
case '+':
current = Repeat(current, accept);
pc.Advance();
break;
case '?':
current = Optional(current, accept);
pc.Advance();
break;
}
f.IsAccepting = false;
f.EpsilonTransitions.Add(current);
break;
default:
ch = pc.Current;
pc.Advance();
next = null;
switch (pc.Current)
{
case '*':
next = new CharFA <TAccept>();
next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
next = Kleene(next, accept);
pc.Advance();
break;
case '+':
next = new CharFA <TAccept>();
next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
next = Repeat(next, accept);
pc.Advance();
break;
case '?':
next = new CharFA <TAccept>();
next.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
next = Optional(next, accept);
pc.Advance();
break;
default:
current = current.FirstAcceptingState as CharFA <TAccept>;
current.IsAccepting = false;
current.Transitions.Add((char)ch, new CharFA <TAccept>(true, accept));
break;
}
if (null != next)
{
current = current.FirstAcceptingState as CharFA <TAccept>;
current.IsAccepting = false;
current.EpsilonTransitions.Add(next);
current = next;
}
break;
}
}
}
internal static LexDocument Parse(ParseContext pc)
{
var result = new LexDocument();
while (-1 != pc.Current)
{
var line = pc.Line;
var column = pc.Column;
var position = pc.Position;
LexNode.SkipCommentsAndWhitespace(pc);
while ('\n' == pc.Current)
{
pc.Advance();
LexNode.SkipCommentsAndWhitespace(pc);
}
var id = LexNode.ParseIdentifier(pc);
if (string.IsNullOrEmpty(id))
{
pc.Advance();
LexNode.SkipCommentsAndWhitespace(pc);
continue;
}
LexNode.SkipCommentsAndWhitespace(pc);
pc.Expecting(':', '-', '=');
if (':' == pc.Current) // attribute set
{
pc.Advance();
var d = new LexAttributeList();
while (-1 != pc.Current && '\n' != pc.Current)
{
var attr = LexAttribute.Parse(pc);
d.Add(attr);
LexNode.SkipCommentsAndWhitespace(pc);
pc.Expecting('\n', ',', -1);
if (',' == pc.Current)
{
pc.Advance();
}
}
result.AttributeSets.Add(id, d);
LexNode.SkipCommentsAndWhitespace(pc);
}
else if ('=' == pc.Current)
{
pc.Advance();
LexNode.SkipCommentsAndWhitespace(pc);
pc.Expecting('\'');
pc.Advance();
var l = pc.CaptureBuffer.Length;
pc.TryReadUntil('\'', '\\', false);
pc.Expecting('\'');
pc.Advance();
var rx = pc.GetCapture(l);
// make sure to capture the line numbers properly:
var rpc = ParseContext.Create(rx);
rpc.EnsureStarted();
rpc.SetLocation(pc.Line, pc.Column, pc.Position);
var rule = new LexRule(id, RegexExpression.Parse(rpc));
rule.SetLocation(line, column, position);
result.Rules.Add(rule);
}
else if ('-' == pc.Current)
{
pc.TrySkipUntil('\n', true);
}
LexNode.SkipCommentsAndWhitespace(pc);
if ('\n' == pc.Current)
{
pc.Advance();
}
}
return(result);
}