string Calculate(ContentExpression expression, EvaluationContext context)
{
var sx = expression as SymbolExpression;
if (sx != null)
{
string[] innerTokens;
var resolvedSymbol = context.ResolveOptional(sx, out innerTokens);
_missingTokens.AddRange(innerTokens);
return(resolvedSymbol);
}
var fx = expression as FunctionCallExpression;
if (fx == null)
{
throw new NotImplementedException("Unknown expression type: " + expression);
}
var argument = Calculate(fx.Argument, context);
var args = fx.Options.Select(opt => Resolve(opt, context)).ToArray();
return(BuiltInFunctions.InvokeOrNull(fx.Function, argument, args));
}
public FunctionCallExpression(bool filterSyntax, string function, ContentExpression argument, params TemplateToken[] options)
{
Options = options;
_filterSyntax = filterSyntax;
Function = function;
Argument = argument;
}
static IEnumerable <SymbolExpression> GetSymbols(ContentExpression expression)
{
var sx = expression as SymbolExpression;
if (sx != null)
{
yield return(sx);
}
else
{
var fx = expression as FunctionCallExpression;
if (fx != null)
{
foreach (var argument in fx.Arguments)
{
foreach (var symbol in GetSymbols(argument))
{
yield return(symbol);
}
}
}
else
{
throw new NotImplementedException("Unknown expression type: " + expression);
}
}
}
string Calculate(ContentExpression expression, EvaluationContext context)
{
var sx = expression as SymbolExpression;
if (sx != null)
{
string[] innerTokens;
var resolvedSymbol = context.ResolveOptional(sx, out innerTokens);
_missingTokens.AddRange(innerTokens);
return(resolvedSymbol);
}
var fx = expression as FunctionCallExpression;
if (fx == null)
{
throw new NotImplementedException("Unknown expression type: " + expression);
}
var args = fx.Arguments.Select(a => Calculate(a, context)).ToArray();
if (args.Any(a => a == null))
{
return(null); // If any argument is undefined, we fail the whole shebang
}
return(BuiltInFunctions.InvokeOrNull(fx.Function, args));
}
public SubstitutionToken(ContentExpression expression)
{
this.expression = expression;
}