/// <summary>
/// Creates a parser with a grammar that matches one or more consecutive characters until any of the specified
/// stop characters are parsed and joins them into a <see cref="string"/>, excluding the stop character.
/// </summary>
/// <param name="stops">The characters at which to stop consuming characters.</param>
/// <returns>A parser with a grammar that consumes consecutive characters until any stop character is parsed
/// or the sequence ends.</returns>
protected IParser<char, string> AnyCharacterUntil(params char[] stops)
{
Contract.Requires(stops != null);
Contract.Requires(stops.Length > 0);
Contract.Ensures(Contract.Result<IParser<char, string>>() != null);
return AnyCharacter.Not(Character(c => stops.Contains(c))).OneOrMore().Join();
}
public void Terminal_Any()
{
var input = "ijk";
var bytes = Encoding.UTF8.GetBytes(input);
var iterator = new ByteInputIterator(bytes);
AExpression any = new Sequence(new AnyCharacter(), new AnyCharacter());
var visitor = new NpegParserVisitor(iterator);
any.Accept(visitor);
Assert.IsTrue(visitor.IsMatch);
Assert.IsTrue(iterator.Index == 2,
"Expected two characters to be consumed and Iterator updated by 2. 0, 1 .. points to 2");
input = "ij";
bytes = Encoding.UTF8.GetBytes(input);
iterator = new ByteInputIterator(bytes);
visitor = new NpegParserVisitor(iterator);
any.Accept(visitor);
Assert.IsTrue(visitor.IsMatch);
Assert.IsTrue(iterator.Index == 2,
"Expected two characters to be consumed and Iterator updated by 2. 0, 1 .. points to 2");
input = "";
bytes = Encoding.UTF8.GetBytes(input);
iterator = new ByteInputIterator(bytes);
any = new AnyCharacter();
visitor = new NpegParserVisitor(iterator);
any.Accept(visitor);
Assert.IsFalse(visitor.IsMatch);
Assert.IsTrue(iterator.Index == 0, "Expected no characters to be consumed and index stay at zero.");
var number = new Sequence(
new OneOrMore(new CharacterClass {
ClassExpression = "[0-9]"
}),
new NotPredicate(
new AnyCharacter()
)
);
input = "012345.";
bytes = Encoding.UTF8.GetBytes(input);
iterator = new ByteInputIterator(bytes);
visitor = new NpegParserVisitor(iterator);
number.Accept(visitor);
Assert.IsFalse(visitor.IsMatch);
}
/// <summary>
/// Creates a parser with a grammar that matches one or more consecutive characters until any of the specified
/// stop words are parsed and joins them into a <see cref="string"/>, excluding the stop word.
/// </summary>
/// <param name="stopWords">The strings at which to stop consuming characters.</param>
/// <returns>A parser with a grammar that consumes consecutive characters until any stop word is parsed
/// or the sequence ends.</returns>
protected IParser<char, string> AnyCharacterUntil(params string[] stopWords)
{
Contract.Requires(stopWords != null);
Contract.Requires(stopWords.Length > 0);
Contract.Ensures(Contract.Result<IParser<char, string>>() != null);
var stops = new List<IParser<char, string>>();
foreach (var word in stopWords)
{
Contract.Assume(!string.IsNullOrEmpty(word));
stops.Add(Word(word));
}
return AnyCharacter.Not(stops.Any()).OneOrMore().Join();
}
public void Terminal_Any()
{
var input = "ijk";
var bytes = Encoding.UTF8.GetBytes(input);
var iterator = new ByteInputIterator(bytes);
AExpression any = new Sequence(new AnyCharacter(), new AnyCharacter());
var visitor = new NpegParserVisitor(iterator);
any.Accept(visitor);
Assert.IsTrue(visitor.IsMatch);
Assert.IsTrue(iterator.Index == 2,
"Expected two characters to be consumed and Iterator updated by 2. 0, 1 .. points to 2");
input = "ij";
bytes = Encoding.UTF8.GetBytes(input);
iterator = new ByteInputIterator(bytes);
visitor = new NpegParserVisitor(iterator);
any.Accept(visitor);
Assert.IsTrue(visitor.IsMatch);
Assert.IsTrue(iterator.Index == 2,
"Expected two characters to be consumed and Iterator updated by 2. 0, 1 .. points to 2");
input = "";
bytes = Encoding.UTF8.GetBytes(input);
iterator = new ByteInputIterator(bytes);
any = new AnyCharacter();
visitor = new NpegParserVisitor(iterator);
any.Accept(visitor);
Assert.IsFalse(visitor.IsMatch);
Assert.IsTrue(iterator.Index == 0, "Expected no characters to be consumed and index stay at zero.");
var number = new Sequence(
new OneOrMore(new CharacterClass {ClassExpression = "[0-9]"}),
new NotPredicate(
new AnyCharacter()
)
);
input = "012345.";
bytes = Encoding.UTF8.GetBytes(input);
iterator = new ByteInputIterator(bytes);
visitor = new NpegParserVisitor(iterator);
number.Accept(visitor);
Assert.IsFalse(visitor.IsMatch);
}
public override void Visit(AnyCharacter expression)
{
_matchStack.Push(
delegate(IInputIterator iterator)
{
// returns true only if this method can consume a character.
if (iterator.Index < iterator.Length)
{
/*
* Consume one character since we're neither at the end of a real string,
* nor operating on the empty string.
*/
iterator.Index += 1;
return(true);
}
else
{
return(false);
}
}
);
}
public virtual void Visit(AnyCharacter expression, T context)
{
}
public abstract void Visit(AnyCharacter expression);
public override void Visit(AnyCharacter expression)
{
_matchStack.Push(
delegate(IInputIterator iterator)
{
// returns true only if this method can consume a character.
if (iterator.Index < iterator.Length)
{
/*
* Consume one character since we're neither at the end of a real string,
* nor operating on the empty string.
*/
iterator.Index += 1;
return true;
}
else
{
return false;
}
}
);
}
public override void Visit(AnyCharacter expression, object context)
{
expressions.Add(expression);
base.Visit(expression, context);
}
public override void Visit(AnyCharacter expression)
{
terminal.Peek().Append('.');
}
public abstract void Visit(AnyCharacter expression);
public override void Visit(AnyCharacter expression)
{
terminal.Peek().Append('.');
}
public void Visit(AnyCharacter expression, Nonterminal context)
{
Add(context, expression, AnyCharacterTerminal.Instance);
}
