static TokenData ScanNewLine(TextInputRange input)
{
input.NewLine();
input.ExtendWhitespaces();
return(new TokenData {
Range = input.Clone(), Type = Token.NewLineIndentation
});
}
// Scan basic double quoted strings
public static IStringLiteral Scan(TextInputRange input)
{
var chr = input.EndChar;
if (!IsDoubleQuote(chr))
{
return(null);
}
input.Extend();
var result = new StringBuilder();
while (true)
{
chr = input.EndChar;
if (chr == '\0')
{
return(null); // file end or invalid input
}
if (IsDoubleQuote(chr))
{
break;
}
if (input.IsEndNewline)
{
input.NewLine();
}
else
{
if (!IsTab(chr) && char.IsControl(chr))
{
HandleControl(input);
}
else
{
if (IsBackslash(chr))
{
if (!HandleEscape(input, result))
{
return(null);
}
}
else
{
result.Append(chr);
input.Extend();
}
}
}
}
input.Extend();
return(new StringLiteral {
Content = result.ToString(), Range = input.Clone()
});
}
/**
* # single line
*
* #<optional>#
* block comments
* #<optional>#
*/
public static bool Scan(TextInputRange range)
{
if (range.EndChar != '#')
{
return(false);
}
do
{
range.Extend();
} while (range.IsEndValid && !range.IsEndNewline && !range.IsEndWhitespace && range.EndChar != '#');
// single line comment
if (range.IsEndNewline)
{
return(true);
}
// is block comment
if (range.EndChar == '#')
{
range.Extend();
var commentMarker = range.Text;
while (range.IsEndValid && range.EndString(commentMarker.Length) != commentMarker)
{
if (range.IsEndNewline)
{
range.NewLine();
}
else
{
range.Extend();
}
}
if (range.EndString(commentMarker.Length) != commentMarker)
{
throw new Exception(message: "Line Comment not Escaped.");
}
range.Extend(commentMarker.Length);
}
else
{
do
{
range.Extend();
} while (range.IsEndValid && !range.IsEndNewline);
}
return(true);
}