} // set during AST construction
#region implemented abstract members of Node
/// <summary>
/// Resolve type defined by this typeExpression. Type Expression must be given in reversed order.
/// </summary>
/// <returns>The resolved type.</returns>
/// <param name="typeExpr">Enumerator of reversed type expresion enumeration.</param>
public static TypeNode RecursiveResolveArrayType <TSymbol>(IEnumerator <IParseTree <TSymbol> > typeExpr) where TSymbol : ISymbol <TSymbol>
{
bool isMutable = ASTBuilder.EatSymbol("mutable", typeExpr);
if (ASTBuilder.EatSymbol("]", typeExpr)) // if ] is present then create ArrayType
{
var resType = new ArrayTypeNode();
resType.IsConstant = !isMutable;
resType.IsFixedSize = false; // we initialize all arrays as dynamic size
if (ASTBuilder.EatSymbol("[", typeExpr)) // opening bracket, no length expression
{
resType.LengthExpression = null;
}
else // length expression present
{
resType.LengthExpression = ExpressionNode.GetExpressionNode(typeExpr.Current);
typeExpr.MoveNext();
Debug.Assert(ASTBuilder.EatSymbol("[", typeExpr)); // eat opening bracket
}
resType.ElementType = RecursiveResolveArrayType(typeExpr);
return(resType);
}
else
{
var resType = new NamedTypeNode();
resType.BuildNode(typeExpr.Current);
resType.IsConstant = !isMutable;
return(resType);
}
}
public static ExpressionNode ResolveOperatorExpression <TSymbol>(IParseTree <TSymbol> parseTree, int opLevel) where TSymbol : ISymbol <TSymbol>
{
if (opLevel > OP_BOTTOM_LEVEL)
{
// these part proceeds op from level 15 to 5
bool isLeft = ASTBuilder.IsLeftOperator(parseTree.Symbol);
// get childrens connected by operators (one level lower)
var childs = isLeft ?
ASTBuilder.Children(parseTree).Reverse().GetEnumerator() : // if left-to-right then reverse arguments
ASTBuilder.Children(parseTree).GetEnumerator();
Debug.Assert(childs.MoveNext()); // set enumerator to the first element (must be present)
return(ParseBinOperator(childs, opLevel - 1, isLeft));
}
else
{
// continue parsing lower level expressions
Debug.Assert(opLevel == OP_BOTTOM_LEVEL); // op level must be 4
var node = ASTBuilder.FirstChild(parseTree); // Operator4Expression -> Operator3Expression
// Operator3Expression -> (prefix_operator)* Operator2Expression
var childs = ASTBuilder.Children(node).Reverse().GetEnumerator();
Debug.Assert(childs.MoveNext());
var op2 = childs.Current; // last child -> Operator2Expression
var op2Childs = ASTBuilder.RevChildrenEnumerator(op2);
Debug.Assert(op2Childs.MoveNext());
return(AddPrefixOperators(3, ParseOperator2(op2Childs), childs));
}
}
} // set during AST construction
#region implemented abstract members of Node
public override void BuildNode <TSymbol>(IParseTree <TSymbol> parseTree)
{
// LoopControl -> ("break" | "continue") (Expression DecimalNumberLiteral?)?
var childs = ASTBuilder.ChildrenArray(parseTree);
Debug.Assert(childs.Length >= 1);
switch (childs[0].Fragment.GetOriginText())
{
case "break":
Mode = LoopControlMode.LCM_BREAK;
break;
case "continue":
Mode = LoopControlMode.LCM_CONTINUE;
break;
}
if (childs.Length >= 2)
{
Value = ExpressionNode.GetExpressionNode(childs[1]);
}
if (childs.Length == 3)
{
Depth = int.Parse(childs[2].Fragment.GetOriginText());
}
}
public override void BuildNode <TSymbol>(IParseTree <TSymbol> parseTree)
{
// DecimalNumberLiteral -> DecimalNumberLiteralToken
// CharacterLiteral -> CharacterLiteralToken
// BooleanLiteral -> BooleanLiteralToken
Value = ASTBuilder.FirstChild(parseTree).Fragment.GetOriginText(); // fill only value - type was set during construction
}
public static ConstNode GetConstNode <TSymbol>(IParseTree <TSymbol> parseTree) where TSymbol : ISymbol <TSymbol>
{
// one of: DecimalNumberLiteral | CharacterLiteral | StringLiteral | BooleanLiteral
TypeNode type;
switch (ASTBuilder.GetName(parseTree.Symbol))
{
case "DecimalNumberLiteral":
type = NamedTypeNode.IntType(true);
break;
case "CharacterLiteral":
type = NamedTypeNode.CharType(true);
break;
case "StringLiteral":
throw new NotImplementedException(); // TODO: strings implementation
case "BooleanLiteral":
type = NamedTypeNode.BoolType(true);
break;
default:
throw new System.ArgumentException();
}
return(new AtomNode(type));
}
public override void BuildNode <TSymbol> (IParseTree <TSymbol> parseTree)
{
var arr = ASTBuilder.ChildrenArray(parseTree);
FieldName = arr [0].Fragment.GetOriginText();
Value = ExpressionNode.GetExpressionNode(arr [2]);
}
} // set during AST construction
#region implemented abstract members of Node
// RecordFieldDefinition.SetProduction(ObjectDeclaration * ";");
// ObjectDeclaration.SetProduction(TypeSpecifier * ObjectName);
public override void BuildNode <TSymbol>(IParseTree <TSymbol> parseTree)
{
IParseTree <TSymbol>[] childs = ASTBuilder.ChildrenArray(parseTree);
// type name
Debug.Assert(childs.Length == 2);
Type = TypeNode.GetTypeNode(childs[0]); // type - arg 0
Name = childs[1].Fragment.GetOriginText(); // name - arg 1
}
// TypeSpecifier -> (TypeName * ("mutable".Optional() * "\\[" * Expression.Optional * "\\]").Star * "mutable".Optional());
public static TypeNode GetTypeNode <TSymbol>(IParseTree <TSymbol> parseTree) where TSymbol : ISymbol <TSymbol>
{
var node = ASTBuilder.AsBranch(parseTree);
var childs = node.Children.Reverse().GetEnumerator();
Debug.Assert(childs.MoveNext());
return(RecursiveResolveArrayType(childs));
}
} // name resolution
#region implemented abstract members of Node
public override void BuildNode <TSymbol> (IParseTree <TSymbol> parseTree)
{
// <recordName> [ <field> ]
var children = ASTBuilder.ChildrenArray(parseTree);
RecordName = children [0].Fragment.GetOriginText();
Field = children [2].Fragment.GetOriginText();
}
public override void BuildNode <TSymbol>(IParseTree <TSymbol> parseTree)
{
// ObjectDefinition -> TypeSpecifier ObjectName "=" Expression
var childs = ASTBuilder.ChildrenArray(parseTree);
Debug.Assert(childs.Length == 4);
Type = TypeNode.GetTypeNode(childs[0]); // type - arg 0
Name = childs[1].Fragment.GetOriginText(); // name - arg 1
Value = ExpressionNode.GetExpressionNode(childs[3]); // value - arg 3
}
public override void BuildNode <TSymbol> (IParseTree <TSymbol> parseTree)
{
Console.WriteLine("Build ast: " + parseTree);
IParseTree <TSymbol>[] childs = ASTBuilder.ChildrenArray(parseTree);
// name { fields }
Debug.Assert(childs.Length == 4);
// name from arg 0
Name = TypeNode.GetTypeNode(childs[0]);
// fields from arg 2
Fields = GetFields(childs[2]);
}
public override void BuildNode <TSymbol> (IParseTree <TSymbol> parseTree)
{
// <type> <name> { <fields> }
var children = ASTBuilder.ChildrenArray(parseTree);
Debug.Assert(children.Length == 5);
Type = TypeNode.GetTypeNode(children[0]); // type - arg 0
Name = children[1].Fragment.GetOriginText(); // name - arg 1
Fields = GetFields(children [3]); // fields - arg 3
}
public override void BuildNode <TSymbol>(IParseTree <TSymbol> parseTree)
{
// IfExpression -> "if" Expression Expression ("else" Expression)?
var childs = ASTBuilder.ChildrenArray(parseTree);
Debug.Assert(childs.Length >= 3);
Condition = ExpressionNode.GetExpressionNode(childs[1]);
Then = ExpressionNode.GetExpressionNode(childs[2]);
if (childs.Length == 5)
{
Else = ExpressionNode.GetExpressionNode(childs[4]);
}
}
} // set during AST construction
#region implemented abstract members of Node
public IEnumerable <RecordVariableFieldDefNode> GetFields <TSymbol> (IParseTree <TSymbol> parseTree) where TSymbol : ISymbol <TSymbol>
{
var lst = new LinkedList <RecordVariableFieldDefNode> ();
var childs = ASTBuilder.ChildrenEnumerator(parseTree);
while (childs.MoveNext())
{
var v = new RecordVariableFieldDefNode();
v.BuildNode(childs.Current);
lst.AddLast(v);
childs.MoveNext(); // skip ',' if present
}
return(lst);
}
// ----- Methods -----
#region implemented abstract members of Node
private IEnumerable <VariableDeclNode> GetParameters <TSymbol>(IParseTree <TSymbol> parseTree) where TSymbol : ISymbol <TSymbol>
{
var parList = new LinkedList <VariableDeclNode>();
var childs = ASTBuilder.ChildrenEnumerator(parseTree);
while (childs.MoveNext())
{
var par = new VariableDeclNode();
par.BuildNode(childs.Current);
parList.AddLast(par);
childs.MoveNext(); // skip ',' if present
}
return(parList);
}
public override void BuildNode <TSymbol>(IParseTree <TSymbol> parseTree)
{
IParseTree <TSymbol>[] childs = ASTBuilder.ChildrenArray(parseTree);
// name ( params ) -> type expr
Debug.Assert(childs.Length == 7);
// name from arg 0
Name = childs[0].Fragment.GetOriginText();
// parameters from arg 2
Parameters = GetParameters(childs[2]);
// type from arg 5
ResultType = TypeNode.GetTypeNode(childs[5]);
// body from arg 6
Body = ExpressionNode.GetExpressionNode(childs[6]);
}
static IEnumerable <RecordTypeFieldDeclarationNode> GetFields <TSymbol>(IParseTree <TSymbol> parseTree)
where TSymbol : ISymbol <TSymbol>
{
var lst = new LinkedList <RecordTypeFieldDeclarationNode>();
var childs = ASTBuilder.ChildrenEnumerator(parseTree);
while (childs.MoveNext())
{
var objectDefinition = ASTBuilder.ChildrenArray(childs.Current) [0];
var fld = new RecordTypeFieldDeclarationNode();
fld.BuildNode(objectDefinition);
lst.AddLast(fld);
}
return(lst);
}
/// <summary>
/// Resolve Expression from ParseTree. Main method.
/// </summary>
public static ExpressionNode GetExpressionNode <TSymbol>(IParseTree <TSymbol> parseTree) where TSymbol : ISymbol <TSymbol>
{
var node = ASTBuilder.FirstChild(parseTree); // Expression -> RecordVariableDefinitionExpression | RecordFieldAccessExpression | OperatorExpression
if (ASTBuilder.GetName(node.Symbol) == "RecordVariableDefinitionExpression")
{
var nod = new RecordVariableDefNode();
nod.BuildNode(node);
return(nod);
}
if (ASTBuilder.GetName(node.Symbol) == "RecordFieldAccessExpression")
{
var nod = new RecordVariableFieldUseNode();
nod.BuildNode(node);
return(nod);
}
node = ASTBuilder.FirstChild(node); // OperatorExpression -> Operator19Expression
node = ASTBuilder.FirstChild(node); // Operator19Expression -> ObjectDefinitionExpression | Operator18Expression
if (ASTBuilder.GetName(node.Symbol) == "ObjectDefinitionExpression") // ObjectDefinition
{
var defNode = new VariableDefNode();
defNode.BuildNode(node);
return(defNode);
}
// Operator18Expression
node = ASTBuilder.FirstChild(node); // IfExpression | WhileExpression | Operator17Expression
switch (ASTBuilder.GetName(node.Symbol))
{
case "IfExpression":
var ifNode = new IfNode();
ifNode.BuildNode(node);
return(ifNode);
case "WhileExpression":
var whileNode = new WhileNode();
whileNode.BuildNode(node);
return(whileNode);
default: // default - Operator17Expression
break;
}
node = ASTBuilder.FirstChild(node); // Operator17Expression -> Operator16Expression
node = ASTBuilder.FirstChild(node); // Operator16Expression -> Operator15Expression
return(ResolveOperatorExpression(node, 15)); // node is operator 15
}
} // set during AST construction
#region implemented abstract members of Node
public override void BuildNode <TSymbol>(IParseTree <TSymbol> parseTree)
{
// Block -> "{" (Expression ";")* "}"
var childs = ASTBuilder.ChildrenEnumerator(parseTree);
childs.MoveNext(); // go to "{"
Debug.Assert(childs.MoveNext()); // enter the brackets
var elems = new List <ExpressionNode>();
while (!ASTBuilder.EatSymbol("}", childs)) // collect expressions until closing "}"
{
elems.Add(ExpressionNode.GetExpressionNode(childs.Current));
childs.MoveNext(); // go to the next symbol
Debug.Assert(ASTBuilder.EatSymbol(";", childs)); // it must be ";"
}
Elements = elems;
}
public static ExpressionNode ResolveAtomicExpression <TSymbol>(IParseTree <TSymbol> parseTree) where TSymbol : ISymbol <TSymbol>
{
// AtomicExpression -> BlockExpression | ObjectDefinitionExpression | ArrayLiteralExpression | ObjectUseExpression |
// IfExpression | WhileExpression | LoopControlExpression
var node = ASTBuilder.FirstChild(parseTree); // AtomicExpression -> one of available symbols
ExpressionNode atomic;
switch (ASTBuilder.GetName(node.Symbol))
{
case "BlockExpression":
atomic = new BlockExpressionNode();
break;
case "ArrayLiteralExpression":
throw new System.NotImplementedException(); // TODO: arrays implementation
case "ObjectUseExpression":
// ObjectUseExpression -> ObjectName | Literals
node = ASTBuilder.FirstChild(node);
if (node.Symbol.IsTerminal) // ObjectName
{
atomic = new VariableUseNode();
}
else // Literals
{
node = ASTBuilder.FirstChild(node); // Literals -> one of available literals
atomic = ConstNode.GetConstNode(node);
}
break;
case "LoopControlExpression":
atomic = new LoopControlNode();
break;
default:
throw new System.ArgumentException();
}
atomic.BuildNode(node);
return(atomic);
}
// ----- Methods -----
#region implemented abstract members of Node
// Program -> (Function|Record)* Eof
public override void BuildNode <TSymbol>(IParseTree <TSymbol> parseTree)
{
var childs = ASTBuilder.ChildrenArray(parseTree);
for (int i = 0; i < childs.Length - 1; i++) // skip last child - it is EOF
{
switch (ASTBuilder.GetName(childs [i].Symbol))
{
case "RecordTypeDeclaration":
var recordNode = new RecordTypeDeclarationNode();
recordNode.BuildNode(childs [i]);
records.AddLast(recordNode);
break;
default:
var funNode = new FunctionDefinitionNode();
funNode.BuildNode(childs [i]);
functions.AddLast(funNode);
break;
}
}
}
/// <summary>
/// Parse one line expression with ++ -- (postfix), function call, array subscript, slice subscript operators.
/// Enumerator must be given with reversed ordering of arguments. This corresponds to Operator2Expression from Grammar.
/// </summary>
public static ExpressionNode ParseOperator2 <TSymbol>(IEnumerator <IParseTree <TSymbol> > opExpr) where TSymbol : ISymbol <TSymbol>
{
// O2 -> O1 ( "++" | "--"
// | "(" (E ",")* E? ")"
// | "[" E "]"
// | "[" E? ".." E? "]"
// )*
if (opExpr.Current.Symbol.IsTerminal)
{
string curText = ASTBuilder.EatTerminal(opExpr);
switch (curText)
{
case "++":
case "--":
return(OperatorNode.BuildUnaryOperator(2, curText, ParseOperator2(opExpr)));
case ")":
var args = new LinkedList <ExpressionNode>();
while (!ASTBuilder.EatSymbol("(", opExpr))
{
ASTBuilder.EatSymbol(",", opExpr); // eat ',' before arg - f(x,y,z,) is also possible
args.AddFirst(GetExpressionNode(opExpr.Current));
opExpr.MoveNext(); // move to next param with ','
}
var res = new FunctionCallNode();
res.Arguments = new List <ExpressionNode>(args);
// TODO: can something return a 'pointer' to function which we can call to execute?
res.Name = opExpr.Current.Fragment.GetOriginText();
return(res);
case "]":
var toExpr = ASTBuilder.EatNonTerminal(opExpr); // slice to or index
bool isSlice = ASTBuilder.EatSymbol("..", opExpr);
var fromExpr = ASTBuilder.EatNonTerminal(opExpr);
Debug.Assert(ASTBuilder.EatSymbol("[", opExpr));
if (isSlice) // slice subscript
{
return(SliceNode.CreateSliceNode(ParseOperator2(opExpr),
GetExpressionOrNull(fromExpr), GetExpressionOrNull(toExpr)));
}
else // array subscript
{
return(ElementNode.Create(ParseOperator2(opExpr), GetExpressionNode(toExpr)));
}
default:
Debug.Assert(false);
break;
}
}
else // non-terminal -> Operator1Expression
{
var op1 = opExpr.Current;
Debug.Assert(!opExpr.MoveNext()); // it must be final symbol in this enumeration
var node = ASTBuilder.FirstChild(op1); // Operator1Expression -> Operator0Expression
// Operator0Expression -> AtomicExpression | "(" Expression ")";
var childs = ASTBuilder.ChildrenEnumerator(node);
Debug.Assert(childs.MoveNext());
if (ASTBuilder.EatSymbol("(", childs))
{
return(GetExpressionNode(childs.Current)); // Expression
}
else // proceed with AtomicExpression
{
return(ResolveAtomicExpression(childs.Current));
}
}
return(null);
}
