void EmitTemplateMethod(IAst ast, TypeBuilder tb, NLiquidDependentPropertyEvalContext context)
{
var compilationUnit = (CompilationUnit)ast;
var methodBuilder = CreatreMethodBuilder(ast, tb);
_variablesMap = new Dictionary <LocalVariableSymbol, Expression>();
_context = context;
//_variablesMap = new Dictionary<LocalVariableSymbol, Expression>(context.PredefinedTypes.DotNetTypesMap);
// the first parameter of tempalte method is TextWriter
var methodParameters = new BlockCollector();
methodParameters.AddVariable(_textWriterParameter);
var commentParameter = EmitCommentParameter(compilationUnit);
if (commentParameter != null)
{
methodParameters.AddVariable(commentParameter);
}
var blockCollector = new BlockCollector();
foreach (var statement in compilationUnit.Statements)
{
EmitStatement(statement, blockCollector);
}
var templateMethod = Expression.Lambda(blockCollector.ToBlockExpression(), methodParameters.Variables);
templateMethod.CompileToMethod(methodBuilder);
}
private void EmitForStatement(For forStmtFor, BlockCollector blockCollector)
{
var forBlockCollector = new BlockCollector();
var collectionExpr = EmitExpression(forStmtFor.ForSource);
var elementType = _context.PredefinedTypes.GetDotNetType(forStmtFor.Symbol.Type);
var enumerableType = typeof(IEnumerable <>).MakeGenericType(elementType);
var enumeratorType = typeof(IEnumerator <>).MakeGenericType(elementType);
var enumeratorVar = Expression.Variable(enumeratorType, "enumerator");
var getEnumeratorCall = Expression.Call(collectionExpr, enumerableType.GetMethod("GetEnumerator", BindingFlags.Instance | BindingFlags.Public));
var enumeratorAssign = Expression.Assign(enumeratorVar, getEnumeratorCall);
blockCollector.AddVariable(enumeratorVar);
// The MoveNext method's actually on IEnumerator, not IEnumerator<T>
var moveNextCall = Expression.Call(enumeratorVar, typeof(IEnumerator).GetMethod("MoveNext", BindingFlags.Instance | BindingFlags.Public));
var breakLabel = Expression.Label("LoopBreak");
var loopVar = Expression.Variable(elementType, forStmtFor.Name.Text);
forBlockCollector.AddVariable(loopVar);
_variablesMap[forStmtFor.Symbol] = loopVar;
forBlockCollector.AddExpression(Expression.Assign(loopVar, Expression.Property(enumeratorVar, "Current")));
EmitStatement(forStmtFor.Body, forBlockCollector);
var loop = Expression.Block(new[] { enumeratorVar },
enumeratorAssign,
Expression.Loop(
Expression.IfThenElse(
Expression.Equal(moveNextCall, Expression.Constant(true)),
forBlockCollector.ToBlockExpression(),
Expression.Break(breakLabel)
),
breakLabel)
);
blockCollector.AddExpression(loop);
}
