/// <summary>
/// Creates a parser which parses a character which satisfies the specified condition.
/// </summary>
/// <param name="expectedChars"></param>
/// <returns></returns>
public static Parser <char> Satisfy(Func <char, bool> satisfies)
{
return
(Create(source =>
ParseResultModule.If(
source.Length >= 1 && satisfies(source[0]),
() => (source[0], source.Substring(1)),
() => source
)));
}
/// <summary>
/// Creates a parser which parses the specified string.
/// </summary>
/// <param name="expectedString"></param>
/// <returns></returns>
public static Parser <string> OfString(string expectedString)
{
return
(Create(source =>
ParseResultModule.If(
source.StartsWith(expectedString),
() => (expectedString, source.Substring(expectedString.Length)),
() => source
)));
}
public Parser <Y> SelectMany <Y>(Func <TValue, Parser <Y> > f)
{
return
(ParserModule.Create(source =>
{
var firstResult = Parse(source);
if (firstResult.IsOk)
{
var secondParser = f(firstResult.Value);
return secondParser.Parse(firstResult.Rest);
}
return ParseResultModule.Error <Y>(source);
}));
}
public Parser <Y> Select <Y>(Func <TValue, Y> func)
{
return
(ParserModule.Create(source =>
{
var result = Parse(source);
return
ParseResultModule.If(
result.IsOk,
() => (func(result.Value), result.Rest),
() => source
);
}));
}
/// <summary>
/// Creates a parser which parses nothing and returns a successful result.
/// </summary>
/// <typeparam name="X"></typeparam>
/// <param name="value"></param>
/// <returns></returns>
public static Parser <X> FromResult <X>(X value)
{
return(Create(source => ParseResultModule.Ok(value, source)));
}