internal static Func <YqlExecutionContext, bool> Compile(YamsterModelQuery query)
{
var compiler = new YqlCompiler(query);
var compiledQuery = compiler.CoerceTo(compiler.CompileNode(query.FilterNode), typeof(bool),
"Expecting a boolean expression");
var filterExpression = Expression.Lambda <Func <YqlExecutionContext, bool> >(
compiledQuery.Expression, compiler.ExecutionContextParameter);
var compiledFunc = filterExpression.Compile();
return(compiledFunc);
}
protected Expression CompileTargetExpression(YqlCompiler compiler, out YqlCompiledNode[] compiledArgs)
{
Type targetType = YamsterModel.GetModelClass(this.TargetObjectType);
Expression targetExpression;
if (TargetObject != null)
{
var compiledTargetObject = compiler.CompileNode(TargetObject);
if (compiledTargetObject.Expression.Type != targetType)
{
ReportError("The target object is " + compiledTargetObject.Expression.Type.Name
+ ", which cannot be converted to " + targetType.Name);
}
targetExpression = compiledTargetObject.Expression;
compiledArgs = new[] { compiledTargetObject };
}
else
{
if (compiler.ModelType != TargetObjectType)
{
ReportError("This expression attempts to retrieve a {0} property from the"
+ " current context item, which is a {1} object",
this.TargetObjectType, compiler.ModelType);
}
switch (compiler.ModelType)
{
case YamsterModelType.Thread:
targetExpression = Expression.Property(compiler.ExecutionContextParameter,
YqlExecutionContext.Info_Thread);
break;
case YamsterModelType.Message:
targetExpression = Expression.Property(compiler.ExecutionContextParameter,
YqlExecutionContext.Info_Message);
break;
default:
throw new NotSupportedException();
}
compiledArgs = new YqlCompiledNode[0];
}
return(targetExpression);
}
