public void Not_Success_ReturnsError()
{
var parser = Parse.Not(Chars.Any());
var result = parser.Parse("xyz");
ParseAssert.ErrorEquals("Unexpected \"x\"", result);
}
public void Not_Error_ReturnsSuccess()
{
var parser = Parse.Not(Chars.String("xyz"));
var result = parser.Parse("x");
ParseAssert.ValueEquals(Unit.Instance, result);
}
/// <summary>
/// Only succeeds when the second parser fails. Returns the result of the first parser.
/// </summary>
public static IParser <TValueA> NotFollowedBy <TValueA, TValueB>(this IParser <TValueA> parserA, IParser <TValueB> parserB)
{
return(from a in parserA
from b in Parse.Not(parserB)
select a);
}