private StatementSyntax LinkAssignment(AssignmentExpressionSyntax assignment, InvocationExpressionSyntax success, InvocationExpressionSyntax failure, Dictionary <string, TypeSyntax> assignments)
{
var leftString = assignment.Left.ToString();
var leftType = Roslyn.SymbolTypeSyntax(_model, assignment.Left);
Debug.Assert(assignment.Left is IdentifierNameSyntax);
Debug.Assert(!assignments.ContainsKey(leftString));
Debug.Assert(leftType != null); //td: error
assignments[leftString] = leftType;
var emptyAssignments = new Dictionary <string, TypeSyntax>();
var right = LinkOperand(assignment.Right, success, failure, emptyAssignments);
Debug.Assert(right != null);
Debug.Assert(!emptyAssignments.Any());
//there are 2 scenarios, first, the right operand was a concurrent expression
//in which case it would have a success function
var successFunc = right
.DescendantNodes()
.OfType <ParenthesizedLambdaExpressionSyntax>()
.Where(fn => fn
.ParameterList
.Parameters
.Any(p => p.Identifier.ToString() == "__res"))
.SingleOrDefault();
if (successFunc != null)
{
return(right.ReplaceNode(successFunc, successFunc
.WithBody(CSharp.Block(new[] {
Templates
.ExpressionAssigment
.Get <StatementSyntax>(assignment.Left, leftType)
}
.Union(successFunc.Body is BlockSyntax
? (successFunc.Body as BlockSyntax)
.Statements
.AsEnumerable()
: new[] { successFunc.Body as StatementSyntax })
.ToArray()))));
}
//else, we need to substitute the actual Right expr by
//an assignment.
var rightString = assignment.Right.ToString();
return(right.ReplaceNodes(right.
DescendantNodes()
.OfType <ExpressionSyntax>()
.Where(node => node.ToString().Equals(rightString)),
(on, nn) => CSharp.AssignmentExpression(
assignment.Kind(),
Templates
.ExpressionProperty
.Get <ExpressionSyntax>(assignment.Left),
nn)));
}
public override SyntaxNode VisitTryStatement(TryStatementSyntax node)
{
_trysInStack++;
try
{
var newNode = (TryStatementSyntax)base.VisitTryStatement(node);
if (_tryConcurrent)
{
var variableName = "__try" + _trysInStack;
_tryVariables.Add(variableName);
//we can only split on expressions directly on the try level
//i.e. no try { if () { EXPRESSION }}
if (_trysInStack > 1 && !(newNode.Parent.Parent is TryStatementSyntax))
{
Debug.Assert(false); //td: error
return(newNode);
}
var statements = new List <StatementSyntax>(newNode.Block.Statements);
var newStatements = new List <StatementSyntax>();
var currentIndex = 0;
while (currentIndex < statements.Count)
{
var oldIndex = currentIndex;
for (int i = oldIndex; i < statements.Count; i++, currentIndex++)
{
var statement = statements[i];
if (statement is YieldStatementSyntax)
{
newStatements.Add(newNode
.WithBlock(CSharp.Block(
statements
.Skip(oldIndex)
.Take(currentIndex - oldIndex - 1))));
//variable and return yield
//td: assert
newStatements.Add(statements[currentIndex - 1]);
newStatements.Add(statements[currentIndex++]);
break;
}
//must make variables available to later code, unless it precedes a yield
var yieldNext = statements.Count > i + 1 && statements[i + 1] is YieldStatementSyntax;
if (statement is LocalDeclarationStatementSyntax && !yieldNext)
{
var decl = statement as LocalDeclarationStatementSyntax;
var varType = decl.Declaration.Type;
if (varType == null || varType.Kind() == SyntaxKind.TypeVarKeyword)
{
varType = Roslyn.SymbolTypeSyntax(_model, decl
.Declaration
.Variables[0]
.Initializer
.Value);
}
Debug.Assert(varType != null, "Untyped local variable on try fix");
var assignmentStatements = new List <StatementSyntax>();
newStatements.Add(decl
.WithDeclaration(decl.Declaration
.WithType(varType)
.WithVariables(CSharp.SeparatedList(
decl
.Declaration
.Variables
.Select(v =>
{
assignmentStatements.Add(CSharp.ExpressionStatement(
CSharp.AssignmentExpression(
SyntaxKind.SimpleAssignmentExpression,
CSharp.IdentifierName(v.Identifier),
v.Initializer.Value)));
return(v.WithInitializer(v
.Initializer
.WithValue(Templates
.DefaultValue
.Get <ExpressionSyntax>(varType))));
})))));
//once moved the variables "up" scope
//we must keep the assignments
Debug.Assert(assignmentStatements.Any());
statements.RemoveAt(i);
statements.InsertRange(i, assignmentStatements);
}
}
}
Debug.Assert(newStatements.Any());
return(LinkTryStatements(newStatements, variableName));
}
return(newNode);
}
finally
{
_trysInStack--;
}
}
