public static RangeSyntax <T> Parse(string text, ScalarParser scalarParser)
{
if (text is null)
{
return(null);
}
if (scalarParser is null)
{
throw new ArgumentNullException(nameof(scalarParser));
}
if (scalarParser(text, out var simpleOperand))
{
return(new UnaryRangeSyntax <T>(UnaryRangeOperator.EqualTo, simpleOperand));
}
var ops = new[] { "<", "<=", ">", ">=" };
for (var i = 0; i < ops.Length; i++)
{
var opText = ops[i];
if (text.StartsWith(opText, StringComparison.Ordinal))
{
var op = (UnaryRangeOperator)(i + 1);
var operandText = text.Substring(opText.Length).Trim();
if (scalarParser(operandText, out var operand))
{
return(new UnaryRangeSyntax <T>(op, operand));
}
}
}
var indexOfDotDot = text.IndexOf("..", StringComparison.Ordinal);
if (indexOfDotDot > 0)
{
var leftText = text.Substring(0, indexOfDotDot).Trim();
var rightText = text.Substring(indexOfDotDot + 2).Trim();
if (scalarParser(leftText, out var left) && scalarParser(rightText, out var right))
{
return(new BinaryRangeSyntax <T>(left, right));
}
}
return(null);
}
protected void SetUp()
{
_parser = new ScalarParser();
_context = XmlMessageTemplateLoader.CreateInitialContext();
}
