public void Visit(Block block)
{
parts.Add(context.GetInnerExpressions(block.Name, value =>
{
context.Push(block, value);
if (typeof(Lambda<string>).BaseType.IsAssignableFrom(value.Type))
{
return
Expression.Call(
Expression.Call(value, value.Type.GetMethod("Invoke"),
Expression.Constant(block.InnerSource())),
typeof(object).GetMethod("ToString"));
}
var visitor = new CompilePartVisitor(context);
visitor.Visit((Section)block);
var expression = CompoundExpression.NullCheck(value,
nullValue: "",
returnIfNotNull: visitor.Result());
context.Pop();
return expression;
}));
}
public IEnumerable<Part> Scan(string template)
{
var regex = MakeRegex(StartDelimiter, EndDelimiter);
var i = 0;
var lineEnded = false;
while (true)
{
Match m;
if ((m = regex.Match(template, i)).Success)
{
var previousLiteral = template.Substring(i, m.Index - i);
var leadingWhiteSpace = m.Groups[1];
var leadingLineEnd = m.Groups[2];
var leadingWhiteSpaceOnly = m.Groups[3];
var marker = m.Groups[4].Value.Trim();
var trailingWhiteSpace = m.Groups[5];
var trailingLineEnd = m.Groups[6];
var isStandalone = (leadingLineEnd.Success || (lineEnded && m.Index == i)) && trailingLineEnd.Success;
Part part = null;
if (marker[0] == '=')
{
var delimiters = DelimitersRegex.Match(marker);
if (delimiters.Success)
{
var start = delimiters.Groups[1].Value;
var end = delimiters.Groups[2].Value;
this.StartDelimiter = start;
this.EndDelimiter = end;
regex = MakeRegex(start, end);
}
}
else if (marker[0] == '#')
{
part = new Block(marker.Substring(1).Trim());
}
else if (marker[0] == '^')
{
part = new InvertedBlock(marker.Substring(1).Trim());
}
else if (marker[0] == '<')
{
part = new TemplateDefinition(marker.Substring(1).Trim());
}
else if (marker[0] == '/')
{
part = new EndSection(marker.Substring(1).Trim());
}
else if (marker[0] == '>')
{
part = new TemplateInclude(marker.Substring(1).Trim(), lineEnded || i == 0 ? leadingWhiteSpaceOnly.Value : null);
}
else if (marker[0] != '!')
{
if (marker == "else")
{
part = new Block(marker);
}
else
{
part = new VariableReference(marker);
isStandalone = false;
}
}
if (!isStandalone)
{
previousLiteral += leadingWhiteSpace;
}
else
{
previousLiteral += leadingLineEnd;
if (part is TemplateInclude)
{
previousLiteral += leadingWhiteSpaceOnly;
}
}
if (previousLiteral != "")
{
yield return new LiteralText(previousLiteral);
}
if (part != null)
{
yield return part;
}
i = m.Index + m.Length;
if (!isStandalone)
{
i -= trailingWhiteSpace.Length;
}
lineEnded = trailingLineEnd.Success;
}
else
{
break;
}
}
if (i < template.Length)
{
var remainingLiteral = template.Substring(i);
yield return new LiteralText(remainingLiteral);
}
}