private static MethodInfo PrepareStringInstanceMethodCall(string methodName, ParseTreeNode root, CompilerState state, out Expression value, out Expression pattern)
{
root.RequireChildren(2);
MethodInfo method;
if (0 == StringComparer.OrdinalIgnoreCase.Compare(methodName, "StartsWith"))
{
method = ReflectionHelper.StringStartsWith;
}
else if (0 == StringComparer.OrdinalIgnoreCase.Compare(methodName, "EndsWith"))
{
method = ReflectionHelper.StringEndsWith;
}
else if (0 == StringComparer.OrdinalIgnoreCase.Compare(methodName, "IndexOf"))
{
method = ReflectionHelper.StringIndexOf;
}
else
{
throw new Exception("Could not find method " + methodName);
}
var arg1Node = root.RequireChild(null, 1, 0, 0);
value = state.ParentRuntime.Analyze(arg1Node, state);
value.RequireString(arg1Node);
var arg2Node = root.RequireChild(null, 1, 0, 1);
pattern = state.ParentRuntime.Analyze(arg2Node, state);
pattern.RequireString(arg2Node);
return method;
}
private Expression Analyze(ParseTree tree, CompilerState state)
{
if (tree == null)
{
throw new ArgumentNullException("tree");
}
if (tree.Status != ParseTreeStatus.Parsed)
{
throw new ArgumentException("Cannot build expression on incomplete tree");
}
var root = tree.Root;
return Analyze(root, state);
}
private Expression BuildBetweenExpression(ParseTreeNode root, CompilerState state)
{
root.RequireChildren(6);
var variableNode = root.ChildNodes[0];
var notOpt = root.RequireChild("notOpt", 1);
root.RequireChild("between", 2);
root.RequireChild("and", 4);
var argument = Analyze(variableNode, state).RemoveNullability();
var leftNode = root.ChildNodes[3];
var leftExpr = Analyze(leftNode, state);
leftExpr.RequireNonVoid(leftNode);
leftExpr = ExpressionTreeExtensions.AdjustReturnType(leftNode, leftExpr, argument.Type);
var rightNode = root.ChildNodes[5];
var rightExpr = Analyze(rightNode, state);
rightExpr.RequireNonVoid(rightNode);
rightExpr = ExpressionTreeExtensions.AdjustReturnType(rightNode, rightExpr, argument.Type);
Expression lower, upper;
if (argument.IsString())
{
lower = ConstantHelper.TryEvalConst(leftNode, PrepareStringComparison(leftNode, leftExpr, argument), Expression.Constant(0), ExpressionType.LessThanOrEqual);
upper = ConstantHelper.TryEvalConst(rightNode, PrepareStringComparison(rightNode, rightExpr, argument), Expression.Constant(0), ExpressionType.GreaterThanOrEqual);
}
else
{
lower = ConstantHelper.TryEvalConst(leftNode, argument, leftExpr, ExpressionType.GreaterThanOrEqual);
upper = ConstantHelper.TryEvalConst(rightNode, argument, rightExpr, ExpressionType.LessThanOrEqual);
}
var result = ConstantHelper.TryEvalConst(root, lower, upper, ExpressionType.AndAlso);
if (notOpt.ChildNodes.Count > 0)
{
result = ConstantHelper.TryEvalConst(root, result, ExpressionType.Not);
}
return result;
}
private Expression BuildInclusionExpression(ParseTreeNode root, Expression leftExpr, string op, CompilerState state)
{
root.RequireChildren(3);
var rightNodeList = ExpressionTreeExtensions.UnwindTupleExprList(root.ChildNodes[2]);
if (rightNodeList.Term.Name == "Id")
{
throw new CompilationException("Parameterized IN statement is not yet supported, consider using function SetContains", rightNodeList);
}
if (rightNodeList.Term.Name != "exprList")
{
throw new CompilationException("Argument for IN operator must be a list of expressions", root);
}
// Expression text is not supposed to be used to pass tens and hundreds of thousands of IDs in plain text.
// Use parameters for large argument sets.
rightNodeList.RequireChildren(1, 1000);
leftExpr = leftExpr.RemoveNullability();
// compile a method to enumerate values in the argument set
var valueEnumerator = ReflectionHelper.EnumerateValues.MakeGenericMethod(leftExpr.Type);
// invoke enumerator, output is a hashset
object matchingSet;
try
{
matchingSet = valueEnumerator.Invoke(null, new object[] {this, rightNodeList, state});
}
catch (TargetInvocationException e)
{
if (e.InnerException == null) throw;
throw e.InnerException;
}
// how many items do we have there?
var countProperty = matchingSet.GetType().GetProperty("Count", BindingFlags.Instance | BindingFlags.Public);
var count = (int) (countProperty.GetValue(matchingSet));
Expression contains;
var leftArgConst = leftExpr as ConstantExpression;
if (leftArgConst != null)
{
// since list is constant and argument is constant, let's just evaluate it
var setContainsMethod = ReflectionHelper.GetOrAddMethod1(matchingSet.GetType(), "Contains", leftExpr.Type);
try
{
contains = Expression.Constant(setContainsMethod.Invoke(matchingSet, new[] {leftArgConst.Value}), typeof(bool));
}
catch (TargetInvocationException e)
{
if (e.InnerException == null) throw;
throw e.InnerException;
}
}
else
{
var threshold = leftExpr.IsInteger() ? 15 : 5;
// for small sets of values, just create a chain of IF/THEN/ELSE statements
if (count <= threshold)
{
var isString = leftExpr.IsString();
var enumeratorMethod = ReflectionHelper.GetOrAddMethod0(matchingSet.GetType(), "GetEnumerator");
IEnumerator enumerator;
try
{
enumerator = (IEnumerator)enumeratorMethod.Invoke(matchingSet, null);
}
catch (TargetInvocationException e)
{
if (e.InnerException == null) throw;
throw e.InnerException;
}
contains = null;
while (enumerator.MoveNext())
{
var next = isString
? PrepareStringEquality(rightNodeList, leftExpr, Expression.Constant(enumerator.Current, leftExpr.Type))
: Expression.Equal(leftExpr, Expression.Constant(enumerator.Current, leftExpr.Type));
contains = contains == null ? next : Expression.OrElse(contains, next);
}
}
else
{
// for larger sets, wire our matchingSet into this expression as constant reference
// it will be kept alive by garbage collector, and will be collected when expression is collected
var setContainsMethod = ReflectionHelper.GetOrAddMethod1(matchingSet.GetType(), "Contains", leftExpr.Type);
contains = Expression.Call(Expression.Constant(matchingSet), setContainsMethod, leftExpr);
}
}
if (op.StartsWith("not "))
{
contains = ConstantHelper.TryEvalConst(root, contains, ExpressionType.Not, typeof(bool));
}
return contains;
}
private Expression BuildIdentifierRootExpression(ParseTreeNode root, CompilerState state)
{
AtomMetadata atom;
var name = root.ChildNodes[0].Token.ValueString;
// first, look for an argument with this name
var argument = state.TryGetArgumentByName(name);
if (argument != null)
{
return argument;
}
var context = state.Context;
// next, see if we have a field or property on the context (if any context present)
var contextBoundExpression = TryGetFieldOrPropertyInfoFromContext(name, context);
if (contextBoundExpression != null)
{
return contextBoundExpression;
}
// and only then look through available IDENTIFIER atoms
if (m_atoms.TryGetValue(name, out atom) && atom.AtomType == AtomType.Identifier)
{
if (atom.ExpressionGenerator != null)
{
return atom.ExpressionGenerator(root, state);
}
if (atom.MethodInfo == null)
{
// internal error, somebody screwed up with configuration of runtime
throw new Exception("ExpressionGenerator and MethodInfo are both null on atom: " + atom.Name);
}
// no arguments? great
var paramInfo = atom.MethodInfo.GetParameters();
if (paramInfo.Length == 0)
{
return BuildFunctorInvokeExpression(atom, (Expression[])null);
}
// any arguments? must have exactly one argument, context must be registered, and context type must be adjustable to this method's arg type
if (context == null)
{
throw new CompilationException("Atom's MethodInfo cannot be used for an Id expression, because context is not available: " + atom.Name, root);
}
Expression adjustedContext;
if (paramInfo.Length > 1 || !ExpressionTreeExtensions.TryAdjustReturnType(root, context, paramInfo[0].ParameterType, out adjustedContext))
{
throw new CompilationException("Atom's MethodInfo may only have either zero arguments or one argument of the same type as expression context: " + atom.Name, root);
}
return BuildFunctorInvokeExpression(atom, adjustedContext);
}
// still nothing found? ask IDENTIFIER atom handlers
foreach (var handler in m_atomHandlers)
{
if (handler.AtomType != AtomType.Identifier)
{
continue;
}
if (handler.ExpressionGenerator == null)
{
// internal error, somebody screwed up with configuration of runtime
throw new Exception("ExpressionGenerator is null on atom handler: " + handler.Name);
}
// only pass the first portion of dot-notation identifier to handler
var result = handler.ExpressionGenerator(root.ChildNodes[0], state);
if (result != null)
{
return result;
}
}
throw new CompilationException("Unknown atom: " + name, root);
}
private Expression BuildIdentifierExpression(ParseTreeNode root, CompilerState state)
{
root.RequireChildren(1, 10);
// first, analyze the first identifier in the dotted sequence
var identifier = BuildIdentifierRootExpression(root, state);
// next, look for any next-level dotted fields and properties
// for these, we will not look into any other atoms or args - only into the reflected fields and properties of the object
for (var i = 1; i < root.ChildNodes.Count; i++)
{
var name = root.ChildNodes[i].Token.Text; // no need to lowercase this text
var next = TryGetFieldOrPropertyInfoFromContext(name, identifier);
if (next == null)
{
throw new CompilationException(string.Format("Could not find field or property {0} on type {1}",
name, identifier.Type));
}
identifier = next;
}
return identifier;
}
private static Expression TopLevelAtomExpressionGeneratorForFields(ParseTreeNode root, CompilerState compilerState)
{
root.RequireChildren(0);
var pqlCompilerState = (PqlCompilerState) compilerState;
var descriptor = pqlCompilerState.ContainerDescriptor;
var parsedRequest = pqlCompilerState.ParsedRequest;
var fieldName = root.Token.ValueString;
var field = descriptor.TryGetField(parsedRequest.TargetEntity.DocumentType, fieldName);
if (field == null)
{
// convention is for handlers to return nulls for unknown atoms
return null;
}
return GetOrAddFieldRefToCompilationContext(parsedRequest, pqlCompilerState, field);
}
private Expression BuildSwitchStatementExpression(CompilerState state, ParseTreeNode caseVariableNode, ParseTreeNode whenThenListNode, Expression caseDefault)
{
var switchVariable = Analyze(caseVariableNode.ChildNodes[0], state);
switchVariable.RequireNonVoid(caseVariableNode.ChildNodes[0]);
if (switchVariable is ConstantExpression)
{
throw new CompilationException("CASE variable should not be a constant value", caseVariableNode);
}
var cases = new List<Tuple<Expression[], Expression, ParseTreeNode>>(whenThenListNode.ChildNodes.Count);
Expression firstNonVoidThen = null;
var mustReturnNullable = false;
foreach (var caseWhenThenNode in whenThenListNode.ChildNodes)
{
caseWhenThenNode.RequireChildren(4);
var whenNodesRoot = ExpressionTreeExtensions.UnwindTupleExprList(caseWhenThenNode.RequireChild(null, 1));
var thenNode = caseWhenThenNode.RequireChild(null, 3);
IList<ParseTreeNode> whenNodes;
if (whenNodesRoot.Term.Name == "exprList")
{
whenNodes = whenNodesRoot.ChildNodes;
}
else
{
whenNodes = new[] { whenNodesRoot };
}
var when = new Expression[whenNodes.Count];
for (var i = 0; i < whenNodes.Count; i++)
{
var whenNode = whenNodes[i];
when[i] = Analyze(whenNode, state);
if (!when[i].IsVoid() && !(when[i] is ConstantExpression))
{
throw new CompilationException("CASE statement with a test variable requires WHEN clauses to be constant values", whenNode);
}
Expression adjusted;
if (ExpressionTreeExtensions.TryAdjustReturnType(whenNode, when[i], switchVariable.Type, out adjusted))
{
when[i] = adjusted;
}
else
{
throw new CompilationException(
string.Format(
"Could not adjust WHEN value type {0} to CASE argument type {1}",
when[i].Type.FullName, switchVariable.Type.FullName), whenNode);
}
}
var then = Analyze(thenNode, state);
cases.Add(new Tuple<Expression[], Expression, ParseTreeNode>(when, then, thenNode));
if (then.IsVoid())
{
// if there is at least one "void" return value, resulting value must be nullable
mustReturnNullable = true;
}
else if (firstNonVoidThen == null)
{
firstNonVoidThen = then;
}
}
if (firstNonVoidThen == null && !caseDefault.IsVoid())
{
firstNonVoidThen = caseDefault;
}
var adjustedCaseDefault = caseDefault;
// now try to adjust whatever remaining VOID "then-s" to the first-met non-void then
// if all THENs are void, then just leave it as-is - type will be adjusted by caller
if (firstNonVoidThen != null)
{
if (mustReturnNullable && firstNonVoidThen.Type.IsValueType && !firstNonVoidThen.IsNullableType())
{
firstNonVoidThen = ExpressionTreeExtensions.MakeNewNullable(
typeof(UnboxableNullable<>).MakeGenericType(firstNonVoidThen.Type),
firstNonVoidThen);
}
for (var i = 0; i < cases.Count; i++)
{
var thenNode = cases[i].Item3;
var then = cases[i].Item2;
if (!ReferenceEquals(then, firstNonVoidThen) && then.IsVoid())
{
Expression adjusted;
if (ExpressionTreeExtensions.TryAdjustReturnType(thenNode, then, firstNonVoidThen.Type, out adjusted))
{
cases[i] = new Tuple<Expression[], Expression, ParseTreeNode>(cases[i].Item1, adjusted, cases[i].Item3);
}
else
{
throw new CompilationException(
string.Format(
"Could not adjust THEN value type {0} to first-met THEN value type {1}",
then.Type.FullName, firstNonVoidThen.Type.FullName), thenNode);
}
}
}
if (caseDefault != null
&& !ExpressionTreeExtensions.TryAdjustReturnType(caseVariableNode, caseDefault, firstNonVoidThen.Type, out adjustedCaseDefault))
{
throw new CompilationException(
string.Format(
"Could not adjust CASE default value's type {0} to first-met THEN value type {1}",
caseDefault.Type.FullName, firstNonVoidThen.Type.FullName), caseVariableNode);
}
}
if (adjustedCaseDefault == null)
{
adjustedCaseDefault = ExpressionTreeExtensions.GetDefaultExpression(
firstNonVoidThen == null
? typeof (UnboxableNullable<ExpressionTreeExtensions.VoidTypeMarker>)
: firstNonVoidThen.Type);
}
return Expression.Switch(
switchVariable, adjustedCaseDefault, null,
cases.Select(x => Expression.SwitchCase(x.Item2, x.Item1)));
}
private Expression BuildNumericConstantExpression(ParseTreeNode root, CompilerState state)
{
root.RequireChildren(0);
var objValue = root.Token.Value;
if (objValue != null && objValue.GetType().IsNumeric())
{
return Expression.Constant(objValue);
}
throw new CompilationException("Invalid numeric constant: " + root.Token.Text, root);
}
private Expression BuildCaseStatementExpression(ParseTreeNode root, CompilerState state)
{
root.RequireChildren(4, 5);
root.RequireChild("CASE", 0);
var caseVariableNode = root.RequireChild("caseVariable", 1);
caseVariableNode.RequireChildren(0, 1);
ParseTreeNode caseDefaultValueNode = null;
if (root.ChildNodes.Count > 4)
{
var caseDefaultNode = root.RequireChild("caseDefault", 3);
if (caseDefaultNode.ChildNodes.Count > 0)
{
caseDefaultNode.RequireChildren(2);
caseDefaultNode.RequireChild("else", 0);
caseDefaultValueNode = caseDefaultNode.RequireChild(null, 1);
}
}
root.RequireChild("END", root.ChildNodes.Count - 1);
// first get the expression for ELSE
var caseDefault = caseDefaultValueNode != null ? Analyze(caseDefaultValueNode, state) : null;
var whenThenListNode = root.RequireChild("caseWhenList", 2);
whenThenListNode.RequireChildren(1, 100);
// now if we don't have an expression to be analyzed, just create a sequence of IIFs
if (caseVariableNode.ChildNodes.Count == 0)
{
return BuildCaseStatementExpression(state, whenThenListNode, caseDefault);
}
// but when there is a variable, type checking has different rules and output is SWITCH statement
return BuildSwitchStatementExpression(state, caseVariableNode, whenThenListNode, caseDefault);
}
private Expression BuildBinaryExpression(ParseTreeNode root, CompilerState state)
{
root.RequireChildren(3);
var leftNode = root.ChildNodes[0];
var leftExpr = Analyze(leftNode, state);
var op = GetBinaryOperator(root.ChildNodes[1]);
if (op == "in" || op == "not in")
{
return BuildInclusionExpression(root, leftExpr, op, state);
}
var rightNode = root.ChildNodes[2];
var rightExpr = Analyze(rightNode, state);
if (!ExpressionTreeExtensions.TryAdjustVoid(ref leftExpr, ref rightExpr))
{
throw new CompilationException("This operation is not defined when both arguments are void", root);
}
Expression expr;
leftExpr = leftExpr.RemoveNullability();
rightExpr = rightExpr.RemoveNullability();
if (leftExpr.IsDateTime() && rightExpr.IsDateTime()
|| leftExpr.IsTimeSpan() && rightExpr.IsTimeSpan())
{
#region DateTime and DateTime, or TimeSpan and TimeSpan
switch (op)
{
case "+":
if (leftExpr.IsDateTime() && rightExpr.IsDateTime())
{
throw new CompilationException("Datetime values cannot be added to one another", root);
}
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Add);
break;
case "-":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Subtract);
break;
case "=":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Equal);
break;
case "!=":
case "<>":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.NotEqual);
break;
case ">":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.GreaterThan);
break;
case "<":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.LessThan);
break;
case "<=":
case "!>":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.LessThanOrEqual);
break;
case ">=":
case "!<":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.GreaterThanOrEqual);
break;
default:
throw new CompilationException("Binary operator not supported for datetime values: " + op, root.ChildNodes[1]);
}
#endregion
}
else if (leftExpr.IsDateTime() && rightExpr.IsTimeSpan())
{
#region DateTime and TimeSpan or TimeSpan and DateTime
switch (op)
{
case "+":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Add);
break;
case "-":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Subtract);
break;
default:
throw new CompilationException("Binary operator not supported for datetime and timespan: " + op, root.ChildNodes[1]);
}
#endregion
}
else if (leftExpr.IsTimeSpan() && rightExpr.IsDateTime())
{
#region TimeSpan and DateTime
switch (op)
{
case "+":
expr = ConstantHelper.TryEvalConst(root, rightExpr, leftExpr, ExpressionType.Add);
break;
default:
throw new CompilationException("Binary operator not supported for timespan and datetime: " + op, root.ChildNodes[1]);
}
#endregion
}
else if (leftExpr.IsString() && rightExpr.IsString())
{
#region String and String
switch (op)
{
case "+":
var concat = ReflectionHelper.StringConcat;
expr = ConstantHelper.TryEvalConst(root, concat, leftExpr, rightExpr);
break;
case "=":
case "!=":
case "<>":
expr = PrepareStringEquality(root, leftExpr, rightExpr);
if (op[0] != '=')
{
expr = ConstantHelper.TryEvalConst(root, expr, ExpressionType.Not, expr.Type);
}
break;
case ">":
expr = ConstantHelper.TryEvalConst(root, PrepareStringComparison(root, leftExpr, rightExpr), Expression.Constant(0), ExpressionType.GreaterThan);
break;
case "<":
expr = ConstantHelper.TryEvalConst(root, PrepareStringComparison(root, leftExpr, rightExpr), Expression.Constant(0), ExpressionType.LessThan);
break;
case "<=":
case "!>":
expr = ConstantHelper.TryEvalConst(root, PrepareStringComparison(root, leftExpr, rightExpr), Expression.Constant(0), ExpressionType.LessThanOrEqual);
break;
case ">=":
case "!<":
expr = ConstantHelper.TryEvalConst(root, PrepareStringComparison(root, leftExpr, rightExpr), Expression.Constant(0), ExpressionType.GreaterThanOrEqual);
break;
case "like":
throw new CompilationException("Instead of LIKE, use predefined functions StartsWith, EndsWith and Contains", root.ChildNodes[1]);
default:
throw new CompilationException("Binary operator not supported for strings: " + op, root.ChildNodes[1]);
}
#endregion
}
else if (leftExpr.IsNumeric() && rightExpr.IsNumeric())
{
#region Numeric and Numeric
ExpressionTreeExtensions.AdjustArgumentsForBinaryOperation(ref leftExpr, ref rightExpr, root);
switch (op)
{
case "+":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Add);
break;
case "-":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Subtract);
break;
case "*":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Multiply);
break;
case "/":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Divide);
break;
case "%":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Modulo);
break;
case "&":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.And);
break;
case "|":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Or);
break;
case "^":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.ExclusiveOr);
break;
case "<":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.LessThan);
break;
case "<=":
case "!>":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.LessThanOrEqual);
break;
case ">":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.GreaterThan);
break;
case ">=":
case "!<":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.GreaterThanOrEqual);
break;
case "=":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Equal);
break;
case "!=":
case "<>":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.NotEqual);
break;
default:
throw new CompilationException("Binary operator not supported yet for numerics: " + op, root.ChildNodes[1]);
}
#endregion
}
else if (leftExpr.IsBoolean() && rightExpr.IsBoolean())
{
#region Boolean and Boolean
switch (op)
{
case "and":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.AndAlso);
break;
case "or":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.OrElse);
break;
case "xor":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.ExclusiveOr);
break;
case "=":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.Equal);
break;
case "!=":
case "<>":
expr = ConstantHelper.TryEvalConst(root, leftExpr, rightExpr, ExpressionType.NotEqual);
break;
default:
throw new CompilationException("Binary operator not supported yet for booleans: " + op, root.ChildNodes[1]);
}
#endregion
}
else
{
throw new CompilationException(string.Format("Binary operator {0} is not yet supported for types {1} and {2}",
op, leftExpr.Type.FullName, rightExpr.Type.FullName), root.ChildNodes[1]);
}
return expr;
}
private object CompileImpl(Expression expression, CompilerState state)
{
if (state == null)
{
throw new ArgumentNullException("state");
}
state.RawReturnType = expression.Type;
while (expression.CanReduce)
{
expression = expression.Reduce();
}
LambdaExpression lambda;
var paramTypes = state.CompileToAction ? new Type[state.Arguments.Count] : new Type[state.Arguments.Count + 1];
for (var i = 0; i < state.Arguments.Count; i++)
{
paramTypes[i] = state.Arguments[i].Type;
}
if (state.CompileToAction)
{
lambda = Expression.Lambda(Expression.GetActionType(paramTypes), expression, state.Arguments);
}
else
{
var returnType = state.ReturnType ?? state.RawReturnType;
paramTypes[paramTypes.Length - 1] = returnType;
expression = ExpressionTreeExtensions.AdjustReturnType(null, expression, returnType);
lambda = Expression.Lambda(expression, state.Arguments);
if (!ReferenceEquals(returnType, lambda.ReturnType))
{
throw new CompilationException(string.Format("Expected return type: {0}. Real return type: {1}", returnType.FullName, lambda.ReturnType.FullName));
}
}
if (lambda.Parameters.Count != state.Arguments.Count)
{
throw new CompilationException(string.Format("Expected number of arguments: {0}. Real number: {1}", state.Arguments.Count, lambda.Parameters.Count));
}
for (var i = 0; i < lambda.Parameters.Count; i++)
{
if (!ReferenceEquals(lambda.Parameters[i].Type, state.Arguments[i].Type))
{
throw new CompilationException(
string.Format("Expected type of argument {0}: {1}. Real type: {2}", i, state.Arguments[i].Type.FullName, lambda.Parameters[i].Type.FullName));
}
}
return lambda.Compile();
}
/// <summary>
/// DO NOT REMOVE! Used implicitly, via generic method instantiation.
/// </summary>
public static HashSet <T> EnumerateValues <T>(IExpressionEvaluatorRuntime runtime, ParseTreeNode root, CompilerState state)
{
if (runtime == null)
{
throw new ArgumentNullException("runtime");
}
if (root == null)
{
throw new ArgumentNullException("root");
}
if (state == null)
{
throw new ArgumentNullException("state");
}
var isString = ReferenceEquals(typeof(T), typeof(string));
var result = isString ? new HashSet <T>((IEqualityComparer <T>)StringComparer.OrdinalIgnoreCase) : new HashSet <T>();
foreach (var childNode in root.ChildNodes)
{
var item = runtime.Analyze(childNode, state);
item.RequireNonVoid(childNode);
try
{
result.Add((T)Convert.ChangeType(((ConstantExpression)item).Value, typeof(T)));
}
catch
{
throw new CompilationException(
String.Format(
"All items in the IN arguments list must be constants of type compatible with {0}. Actual expression found: {1}, of type {2}",
typeof(T).FullName, item.NodeType, item.Type), childNode);
}
}
return(result);
}
private static Expression TopLevelAtomExpressionGeneratorForParameters(ParseTreeNode root, CompilerState compilerState)
{
root.RequireChildren(0);
var pqlCompilerState = (PqlCompilerState) compilerState;
var parsedRequest = pqlCompilerState.ParsedRequest;
var names = pqlCompilerState.RequestParameters.Names;
var paramName = root.Token.ValueString;
if (string.IsNullOrEmpty(paramName) || paramName[0] != '@')
{
// convention is for handlers to return nulls for unknown atoms
return null;
}
if (names != null)
{
for (var ordinal = 0; ordinal < names.Length; ordinal++)
{
if (0 == StringComparer.OrdinalIgnoreCase.Compare(names[ordinal], paramName))
{
return GetOrAddParameterRefToCompilationContext(parsedRequest, pqlCompilerState, ordinal);
}
}
}
throw new CompilationException("Undefined parameter: " + paramName, root);
}
private Expression BuildIsNullPredicate(ParseTreeNode root, CompilerState state, bool compareIsNull)
{
var value = state.ParentRuntime.Analyze(root, state);
// IS NULL
if (compareIsNull)
{
return value.Type.IsNullableType()
? ConstantHelper.TryEvalConst(root, ConstantHelper.TryEvalConst(root, value.Type.GetField("HasValue"), value), ExpressionType.Not, typeof (bool))
: value.Type.IsValueType
? Expression.Constant(false)
: ConstantHelper.TryEvalConst(root, value, Expression.Constant(null), ExpressionType.Equal);
}
// IS NOT NULL
return value.Type.IsNullableType()
? ConstantHelper.TryEvalConst(root, value.Type.GetField("HasValue"), value)
: value.Type.IsValueType
? Expression.Constant(true)
: ConstantHelper.TryEvalConst(root, value, Expression.Constant(null), ExpressionType.NotEqual);
}
private Expression BuildCaseStatementExpression(CompilerState state, ParseTreeNode whenThenListNode, Expression caseDefault)
{
// now start building on top of the tail, right to left,
// also making sure that types are compatible
var tail = caseDefault;
for (var i = whenThenListNode.ChildNodes.Count - 1; i >= 0; i--)
{
var caseWhenThenNode = whenThenListNode.RequireChild("caseWhenThen", i);
caseWhenThenNode.RequireChildren(4);
var whenNode = caseWhenThenNode.RequireChild(null, 1);
var thenNode = caseWhenThenNode.RequireChild(null, 3);
if (whenNode.Term.Name == "tuple")
{
throw new CompilationException("When variable for CASE is not specified, you can only have one expression in each WHEN clause", whenNode);
}
// in this flavor of CASE, we are building a sequence of IIFs
// it requires that our "WHEN" clause is of non-nullable boolean type
var when = Analyze(whenNode, state).RemoveNullability();
when.RequireBoolean(whenNode);
var then = Analyze(thenNode, state);
// try to auto-adjust types of this "THEN" and current tail expression if needed
if (tail != null)
{
Expression adjusted;
if (ExpressionTreeExtensions.TryAdjustReturnType(thenNode, then, tail.Type, out adjusted))
{
then = adjusted;
}
else if (ExpressionTreeExtensions.TryAdjustReturnType(thenNode, tail, then.Type, out adjusted))
{
tail = adjusted;
}
else
{
throw new CompilationException(
string.Format(
"Incompatible types within CASE statement. Tail is of type {0}, and then is of type {1}",
tail.Type.FullName, then.Type.FullName), thenNode);
}
}
if (when is ConstantExpression)
{
if ((bool) ((ConstantExpression) when).Value)
{
tail = then;
}
}
else
{
tail = Expression.Condition(when, then, tail ?? ExpressionTreeExtensions.GetDefaultExpression(then.Type));
}
}
return tail;
}
private Expression BuildFunCallExpression(ParseTreeNode root, CompilerState state)
{
// funCall -> Id
var idNode = root.RequireChild("Id", 0);
idNode.RequireChildren(1); // dotted identifiers are not supported for function calls
// funCall -> funArgs
root.RequireChild("funArgs", 1);
AtomMetadata atom;
var name = idNode.ChildNodes[0].Token.ValueString;
if (!m_atoms.TryGetValue(name, out atom) || atom.AtomType != AtomType.Function)
{
throw new CompilationException("Unknown function: " + name, root);
}
if (atom.MethodInfo != null)
{
return BuildFunCallExpressionFromMethodInfo(atom, root, state);
}
if (atom.ExpressionGenerator != null)
{
return atom.ExpressionGenerator(root, state);
}
// internal error, somebody screwed up with configuration of runtime
throw new Exception("ExpressionGenerator and MethodInfo are both null on atom: " + atom.Name);
}
private Expression BuildStringLiteralExpression(ParseTreeNode root, CompilerState state)
{
root.RequireChildren(0);
var value = root.Token.ValueString;
var expr = string.IsNullOrEmpty(value)
? Expression.Constant(null, typeof (String)) : Expression.Constant(PreprocessStringLiteral(value, root));
return expr;
}
private Expression BuildFunCallExpressionFromMethodInfo(AtomMetadata atom, ParseTreeNode root, CompilerState state)
{
// number of arguments must exactly match number of child nodes in the tree
var paramInfo = atom.MethodInfo.GetParameters();
var funArgs = root.RequireChild("exprList", 1, 0);
funArgs.RequireChildren(paramInfo.Length);
// types and order of arguments must match nodes in the tree
var args = new Expression[paramInfo.Length];
for (var i = 0; i < paramInfo.Length; i++)
{
var param = paramInfo[i];
var argNode = funArgs.ChildNodes[i];
var value = state.ParentRuntime.Analyze(argNode, state);
Expression adjusted;
if (!ExpressionTreeExtensions.TryAdjustReturnType(root, value, param.ParameterType, out adjusted))
{
throw new CompilationException(string.Format("Could not adjust parameter number {0} to invoke function {1}",
i, atom.Name), funArgs.ChildNodes[i]);
}
args[i] = adjusted;
}
return BuildFunctorInvokeExpression(atom, args);
}
private Expression BuildUnaryExpression(ParseTreeNode root, CompilerState state)
{
root.RequireChildren(2, 4);
ParseTreeNode targetNode;
string op;
if (root.ChildNodes.Count == 2)
{
targetNode = root.ChildNodes[1];
op = root.ChildNodes[0].Token.ValueString;
}
else
{
// we should have IS NULL or IS NOT NULL operator here
targetNode = root.ChildNodes[0];
var k1 = root.RequireChild("is", 1).Term.Name;
var k2 = root.RequireChild(null, 2).Term.Name;
var k3 = root.ChildNodes.Count == 4 ? root.RequireChild(null, 3).Term.Name : null;
if (0 != StringComparer.OrdinalIgnoreCase.Compare(k1, "is")
|| (k3 == null && 0 != StringComparer.OrdinalIgnoreCase.Compare(k2, "null"))
|| (k3 != null && (0 != StringComparer.OrdinalIgnoreCase.Compare(k2, "not") || 0 != StringComparer.OrdinalIgnoreCase.Compare(k3, "null")))
)
{
throw new CompilationException("IS NULL or IS NOT NULL expected", root);
}
op = k3 == null ? "is null" : "is not null";
}
switch (op)
{
case "-":
{
var target = Analyze(targetNode, state).RemoveNullability();
target.RequireNumeric(targetNode);
return ConstantHelper.TryEvalConst(root, target, ExpressionType.Negate, target.Type);
}
case "+":
{
var target = Analyze(targetNode, state).RemoveNullability();
target.RequireNumeric(targetNode);
return target;
}
case "~":
{
var target = Analyze(targetNode, state).RemoveNullability();
target.RequireInteger(targetNode);
return ConstantHelper.TryEvalConst(root, target, ExpressionType.Not, target.Type);
}
case "is null":
return BuildIsNullPredicate(targetNode, state, true);
case "is not null":
return BuildIsNullPredicate(targetNode, state, false);
default:
{
var target = Analyze(targetNode, state).RemoveNullability();
if (0 == StringComparer.OrdinalIgnoreCase.Compare("not", op))
{
target.RequireBoolean(targetNode);
return ConstantHelper.TryEvalConst(root, target, ExpressionType.Not, target.Type);
}
throw new CompilationException(
string.Format(
"Unary operator {0} not supported for type {1}", op, target.Type.FullName), root);
}
}
}
private static Expression PredefinedAtom_RowNumberInPage(ParseTreeNode root, CompilerState compilerState)
{
var funArgs = ExpressionTreeExtensions.UnwindTupleExprList(root.RequireChild("funArgs", 1));
funArgs.RequireChildren(0);
return Expression.Field(compilerState.Context, "RowNumberInOutput");
}