private Result RewriteNewArrayExpression(Expression expr, Stack stack)
{
var node = (NewArrayExpression)expr;
if (node.NodeType == ExpressionType.NewArrayInit)
{
// In a case of array construction with element initialization
// the element expressions are never emitted on an empty stack because
// the array reference and the index are on the stack.
stack = Stack.NonEmpty;
}
else
{
// In a case of NewArrayBounds we make no modifications to the stack
// before emitting bounds expressions.
}
var cr = new ChildRewriter(this, stack, node.Expressions.Count);
cr.Add(node.Expressions);
if (cr.Rewrite)
{
expr = NewArrayExpression.Make(node.NodeType, node.Type, new TrueReadOnlyCollection <Expression>(cr[0, -1]));
}
return(cr.Finish(expr));
}
/// <summary>
/// Creates a new array expression of the specified type from the provided initializers.
/// </summary>
/// <param name="type">A Type that represents the element type of the array.</param>
/// <param name="initializers">The expressions used to create the array elements.</param>
/// <returns>An instance of the <see cref="NewArrayExpression"/>.</returns>
public static NewArrayExpression NewArrayInit(Type type, IEnumerable <Expression> initializers)
{
ContractUtils.RequiresNotNull(type, "type");
ContractUtils.RequiresNotNull(initializers, "initializers");
if (type.Equals(typeof(void)))
{
throw Error.ArgumentCannotBeOfTypeVoid();
}
ReadOnlyCollection <Expression> initializerList = initializers.ToReadOnly();
Expression[] newList = null;
for (int i = 0, n = initializerList.Count; i < n; i++)
{
Expression expr = initializerList[i];
RequiresCanRead(expr, "initializers");
if (!TypeUtils.AreReferenceAssignable(type, expr.Type))
{
if (TypeUtils.IsSameOrSubclass(typeof(LambdaExpression), type) && type.IsAssignableFrom(expr.GetType()))
{
expr = Expression.Quote(expr);
}
else
{
throw Error.ExpressionTypeCannotInitializeArrayType(expr.Type, type);
}
if (newList == null)
{
newList = new Expression[initializerList.Count];
for (int j = 0; j < i; j++)
{
newList[j] = initializerList[j];
}
}
}
if (newList != null)
{
newList[i] = expr;
}
}
if (newList != null)
{
initializerList = new TrueReadOnlyCollection <Expression>(newList);
}
return(NewArrayExpression.Make(ExpressionType.NewArrayInit, type.MakeArrayType(), initializerList));
}
/// <summary>
/// Creates a <see cref="NewArrayExpression"/> that represents creating an array that has a specified rank.
/// </summary>
/// <param name="type">A <see cref="Type"/> that represents the element type of the array.</param>
/// <param name="bounds">An IEnumerable{T} that contains Expression objects to use to populate the Expressions collection.</param>
/// <returns>A <see cref="NewArrayExpression"/> that has the <see cref="P:NodeType"/> property equal to type and the <see cref="P:Expressions"/> property set to the specified value.</returns>
public static NewArrayExpression NewArrayBounds(Type type, IEnumerable <Expression> bounds)
{
ContractUtils.RequiresNotNull(type, "type");
ContractUtils.RequiresNotNull(bounds, "bounds");
if (type.Equals(typeof(void)))
{
throw Error.ArgumentCannotBeOfTypeVoid();
}
ReadOnlyCollection <Expression> boundsList = bounds.ToReadOnly();
int dimensions = boundsList.Count;
if (dimensions <= 0)
{
throw Error.BoundsCannotBeLessThanOne();
}
for (int i = 0; i < dimensions; i++)
{
Expression expr = boundsList[i];
RequiresCanRead(expr, "bounds");
if (!TypeUtils.IsInteger(expr.Type))
{
throw Error.ArgumentMustBeInteger();
}
}
Type arrayType;
if (dimensions == 1)
{
//To get a vector, need call Type.MakeArrayType().
//Type.MakeArrayType(1) gives a non-vector array, which will cause type check error.
arrayType = type.MakeArrayType();
}
else
{
arrayType = type.MakeArrayType(dimensions);
}
return(NewArrayExpression.Make(ExpressionType.NewArrayBounds, arrayType, bounds.ToReadOnly()));
}