/// <summary>
/// If the result is empty, format the fragment of text describing the error.
/// </summary>
/// <returns>The error fragment.</returns>
public string FormatErrorMessageFragment()
{
if (ErrorMessage != null)
{
return(ErrorMessage);
}
string message;
if (Location.IsAtEnd)
{
message = "unexpected end of input";
}
else
{
var next = Location.ConsumeChar().Value;
message = $"unexpected {Display.Presentation.FormatLiteral(next)}";
}
if (Expectations != null)
{
var expected = Friendly.List(Expectations);
message += $", expected {expected}";
}
return(message);
}
/// <summary>
/// If the result is empty, format the fragment of text describing the error.
/// </summary>
/// <returns>The error fragment.</returns>
public string FormatErrorMessageFragment()
{
if (ErrorMessage != null)
{
return(ErrorMessage);
}
string message;
if (Remainder.IsAtEnd)
{
message = "unexpected end of input";
}
else
{
var next = Remainder.ConsumeChar().Value;
message = $"unexpected `{next}`";
}
if (Expectations != null)
{
var expected = Friendly.List(Expectations);
message += $", expected {expected}";
}
return(message);
}
public void FriendlyListsPreserveOrderButRemoveDuplicates()
{
var actual = Friendly.List(new[] { "one", "two", "two", "one", "three" });
const string expected = "one, two or three";
Assert.Equal(expected, actual);
}
/// <summary>
/// If the result is empty, format the fragment of text describing the error.
/// </summary>
/// <returns>The error fragment.</returns>
public string FormatErrorMessageFragment()
{
if (ErrorMessage != null)
{
return(ErrorMessage);
}
string message;
if (Remainder.IsAtEnd)
{
message = "unexpected end of input";
}
else
{
var next = Remainder.ConsumeToken().Value;
var appearance = Presentation.FormatAppearance(next.Kind, next.ToStringValue());
message = $"unexpected {appearance}";
}
if (Expectations != null)
{
var expected = Friendly.List(Expectations);
message += $", expected {expected}";
}
return(message);
}
/// <summary>
/// Parse any single character except those in <paramref name="chars"/>.
/// </summary>
public static TextParser <char> ExceptIn(params char[] chars)
{
return(Matching(c => !chars.Contains(c), "any character except " + Friendly.List(chars.Select(Presentation.FormatLiteral))));
}