Michael Schimmel
752 lines
27 KiB
ObjectPascal
752 lines
27 KiB
ObjectPascal
unit Myc.Ast.Binding;
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interface
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uses
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System.SysUtils,
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System.Classes,
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System.Generics.Collections,
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Myc.Data.Scalar,
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Myc.Data.Value,
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Myc.Ast.Nodes,
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Myc.Ast.Visitor,
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Myc.Ast.Scope,
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Myc.Ast.Analyzer,
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Myc.Ast;
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type
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IAstBinder = interface(IAstVisitor)
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function Execute(const RootNode: IAstNode; out Descriptor: IScopeDescriptor): IAstNode;
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end;
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TAstBinder = class; // Forward declaration
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// This visitor handles the expansion of a single macro body (` `...`).
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TExpansionVisitor = class(TAstTransformer)
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private
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FBinder: TAstBinder;
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FMacroScope: IExecutionScope;
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function TransformAndSpliceNodes(const ANodes: TArray<IAstNode>): TArray<IAstNode>;
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protected
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function VisitUnquote(const Node: IUnquoteNode): TDataValue; override;
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function VisitUnquoteSplicing(const Node: IUnquoteSplicingNode): TDataValue; override;
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function VisitFunctionCall(const Node: IFunctionCallNode): TDataValue; override;
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function VisitBlockExpression(const Node: IBlockExpressionNode): TDataValue; override;
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public
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constructor Create(const ABinder: TAstBinder; const AMacroScope: IExecutionScope);
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end;
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TAstBinder = class(TAstTransformer, IAstBinder)
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private
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type
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TUpvalueMapping = class
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public
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Map: TDictionary<TResolvedAddress, Integer>;
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Nodes: TList<IIdentifierNode>;
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constructor Create;
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destructor Destroy; override;
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end;
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private
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FInitialScope: IExecutionScope;
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FCurrentDescriptor: IScopeDescriptor;
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FUpvalueStack: TStack<TUpvalueMapping>;
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FNestedLambdaCount: Integer;
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FIsTailStack: TStack<Boolean>;
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FNextIsTail: Boolean;
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FBoxedDeclarations: THashSet<IVariableDeclarationNode>;
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FEvaluatorFactory: TEvaluatorFactory;
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// Operator folding maps
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FBinaryOperators: TDictionary<string, TScalar.TBinaryOp>;
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FUnaryOperators: TDictionary<string, TScalar.TUnaryOp>;
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procedure EnterScope;
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procedure ExitScope;
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function IsValidIdentifier(const Name: string): Boolean;
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function EvaluateAtCompileTime(const ANode: IAstNode): TDataValue;
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protected
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function Accept(const Node: IAstNode): TDataValue; override;
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function VisitIdentifier(const Node: IIdentifierNode): TDataValue; override;
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function VisitVariableDeclaration(const Node: IVariableDeclarationNode): TDataValue; override;
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function VisitAssignment(const Node: IAssignmentNode): TDataValue; override;
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function VisitLambdaExpression(const Node: ILambdaExpressionNode): TDataValue; override;
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function VisitMacroDefinition(const Node: IMacroDefinitionNode): TDataValue; override;
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function VisitFunctionCall(const Node: IFunctionCallNode): TDataValue; override;
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function VisitMacroExpansionNode(const Node: IMacroExpansionNode): TDataValue; override;
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function VisitRecurNode(const Node: IRecurNode): TDataValue; override;
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function VisitBlockExpression(const Node: IBlockExpressionNode): TDataValue; override;
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function VisitIfExpression(const Node: IIfExpressionNode): TDataValue; override;
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function VisitTernaryExpression(const Node: ITernaryExpressionNode): TDataValue; override;
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function VisitBinaryExpression(const Node: IBinaryExpressionNode): TDataValue; override;
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function VisitUnaryExpression(const Node: IUnaryExpressionNode): TDataValue; override;
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public
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constructor Create(const AInitialScope: IExecutionScope; const AEvaluatorFactory: TEvaluatorFactory);
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destructor Destroy; override;
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function Execute(const RootNode: IAstNode; out Descriptor: IScopeDescriptor): IAstNode;
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end;
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TBoundIdentifierNode = class(TIdentifierNode)
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private
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FAddress: TResolvedAddress;
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public
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constructor Create(const AUnboundNode: IIdentifierNode; const AAddress: TResolvedAddress);
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property Address: TResolvedAddress read FAddress;
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end;
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TBoundVariableDeclarationNode = class(TVariableDeclarationNode)
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private
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FIsBoxed: Boolean;
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public
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constructor Create(const AIdentifier: IIdentifierNode; AInitializer: IAstNode; AIsBoxed: Boolean);
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property IsBoxed: Boolean read FIsBoxed;
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end;
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TBoundLambdaExpressionNode = class(TLambdaExpressionNode)
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private
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FScopeDescriptor: IScopeDescriptor;
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FUpvalues: TArray<TResolvedAddress>;
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FHasNestedLambdas: Boolean;
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public
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constructor Create(
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const AUnboundNode: ILambdaExpressionNode;
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const ABody: IAstNode;
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const AParameters: TArray<IIdentifierNode>;
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const AScopeDescriptor: IScopeDescriptor;
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const AUpvalues: TArray<TResolvedAddress>;
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AHasNestedLambdas: Boolean
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);
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property ScopeDescriptor: IScopeDescriptor read FScopeDescriptor;
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property Upvalues: TArray<TResolvedAddress> read FUpvalues;
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property HasNestedLambdas: Boolean read FHasNestedLambdas;
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end;
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TBoundFunctionCallNode = class(TFunctionCallNode)
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private
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FIsTailCall: Boolean;
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public
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constructor Create(
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const AUnboundNode: IFunctionCallNode;
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const ACallee: IAstNode;
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const AArguments: TArray<IAstNode>;
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AIsTailCall: Boolean
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);
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property IsTailCall: Boolean read FIsTailCall;
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end;
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implementation
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uses
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System.Generics.Defaults,
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System.Character;
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type
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TResolvedAddressComparer = class(TEqualityComparer<TResolvedAddress>)
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public
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function Equals(const Left, Right: TResolvedAddress): Boolean; override;
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function GetHashCode(const Value: TResolvedAddress): Integer; override;
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end;
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{ TExpansionVisitor }
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constructor TExpansionVisitor.Create(const ABinder: TAstBinder; const AMacroScope: IExecutionScope);
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begin
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inherited Create;
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FBinder := ABinder;
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FMacroScope := AMacroScope;
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end;
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function TExpansionVisitor.TransformAndSpliceNodes(const ANodes: TArray<IAstNode>): TArray<IAstNode>;
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var
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newList: TList<IAstNode>;
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nodeToSplice: IAstNode;
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begin
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newList := TList<IAstNode>.Create;
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try
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for var node in ANodes do
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begin
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if (node is TUnquoteSplicingNode) then
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begin
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var spliceExpr := (node as TUnquoteSplicingNode).Expression;
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var evaluatedSpliceValue := VisitUnquote(TAst.Unquote(spliceExpr));
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if (not evaluatedSpliceValue.IsVoid) and (evaluatedSpliceValue.Kind = vkInterface) then
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begin
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nodeToSplice := evaluatedSpliceValue.AsIntf<IAstNode>;
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if (nodeToSplice is TBlockExpressionNode) then
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newList.AddRange((nodeToSplice as TBlockExpressionNode).Expressions)
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else
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raise Exception.Create('Expression inside unquote-splicing (`~@`) must be a list of nodes (a block).');
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end
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else
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raise Exception.Create('Expression inside unquote-splicing (`~@`) must evaluate to a list of nodes (a block).');
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end
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else
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begin
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var transformedValue := node.Accept(self);
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if not transformedValue.IsVoid then
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newList.Add(transformedValue.AsIntf<IAstNode>);
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end;
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end;
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Result := newList.ToArray;
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finally
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newList.Free;
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end;
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end;
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function TExpansionVisitor.VisitUnquote(const Node: IUnquoteNode): TDataValue;
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var
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value: TDataValue;
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expr: IAstNode;
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addr: TResolvedAddress;
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begin
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expr := Node.Expression;
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if (expr is TIdentifierNode) then
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begin
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addr := FMacroScope.CreateDescriptor.FindSymbol((expr as TIdentifierNode).Name);
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if (addr.Kind = akLocalOrParent) and (addr.ScopeDepth = 0) then
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begin
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var argValue := FMacroScope.Values[addr];
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if argValue.Kind = vkInterface then
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begin
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Result := argValue;
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exit;
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end;
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end;
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end;
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value := FBinder.EvaluateAtCompileTime(expr);
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if value.Kind in [vkScalar, vkText, vkVoid] then
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Result := TDataValue.FromIntf<IAstNode>(TAst.Constant(value))
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else
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raise Exception.CreateFmt('Cannot unquote complex value of type %s at compile time.', [value.Kind.ToString]);
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end;
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function TExpansionVisitor.VisitUnquoteSplicing(const Node: IUnquoteSplicingNode): TDataValue;
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begin
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raise Exception.Create('Unquote-splicing (`~@`) can only appear inside a list form (e.g., a function call or a `do` block).');
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end;
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function TExpansionVisitor.VisitFunctionCall(const Node: IFunctionCallNode): TDataValue;
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var
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newArgs: TArray<IAstNode>;
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transformedCallee: IAstNode;
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begin
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transformedCallee := Self.Accept(Node.Callee).AsIntf<IAstNode>;
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newArgs := TransformAndSpliceNodes(Node.Arguments);
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Result := TDataValue.FromIntf<IFunctionCallNode>(TAst.FunctionCall(transformedCallee, newArgs));
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end;
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function TExpansionVisitor.VisitBlockExpression(const Node: IBlockExpressionNode): TDataValue;
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var
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newExprs: TArray<IAstNode>;
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begin
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newExprs := TransformAndSpliceNodes(Node.Expressions);
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Result := TDataValue.FromIntf<IBlockExpressionNode>(TAst.Block(newExprs));
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end;
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{ TBoundIdentifierNode }
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constructor TBoundIdentifierNode.Create(const AUnboundNode: IIdentifierNode; const AAddress: TResolvedAddress);
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begin
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inherited Create(AUnboundNode.Name);
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FAddress := AAddress;
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end;
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{ TBoundVariableDeclarationNode }
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constructor TBoundVariableDeclarationNode.Create(const AIdentifier: IIdentifierNode; AInitializer: IAstNode; AIsBoxed: Boolean);
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begin
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inherited Create(AIdentifier, AInitializer);
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FIsBoxed := AIsBoxed;
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end;
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{ TBoundLambdaExpressionNode }
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constructor TBoundLambdaExpressionNode.Create(
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const AUnboundNode: ILambdaExpressionNode;
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const ABody: IAstNode;
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const AParameters: TArray<IIdentifierNode>;
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const AScopeDescriptor: IScopeDescriptor;
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const AUpvalues: TArray<TResolvedAddress>;
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AHasNestedLambdas: Boolean
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);
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begin
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inherited Create(AParameters, ABody);
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FScopeDescriptor := AScopeDescriptor;
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FUpvalues := AUpvalues;
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FHasNestedLambdas := AHasNestedLambdas;
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end;
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{ TBoundFunctionCallNode }
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constructor TBoundFunctionCallNode.Create(
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const AUnboundNode: IFunctionCallNode;
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const ACallee: IAstNode;
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const AArguments: TArray<IAstNode>;
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AIsTailCall: Boolean
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);
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begin
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inherited Create(ACallee, AArguments);
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FIsTailCall := AIsTailCall;
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end;
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{ TResolvedAddressComparer }
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function TResolvedAddressComparer.Equals(const Left, Right: TResolvedAddress): Boolean;
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begin
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Result := (Left = Right);
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end;
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function TResolvedAddressComparer.GetHashCode(const Value: TResolvedAddress): Integer;
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begin
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Result := 17;
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Result := Result * 23 + Ord(Value.Kind);
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Result := Result * 23 + Value.ScopeDepth;
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Result := Result * 23 + Value.SlotIndex;
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end;
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{ TAstBinder.TUpvalueMapping }
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constructor TAstBinder.TUpvalueMapping.Create;
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begin
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inherited Create;
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Map := TDictionary<TResolvedAddress, Integer>.Create(TResolvedAddressComparer.Create);
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Nodes := TList<IIdentifierNode>.Create();
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end;
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destructor TAstBinder.TUpvalueMapping.Destroy;
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begin
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Nodes.Free;
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Map.Free;
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inherited Destroy;
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end;
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{ TAstBinder }
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constructor TAstBinder.Create(const AInitialScope: IExecutionScope; const AEvaluatorFactory: TEvaluatorFactory);
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var
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op: TScalar.TBinaryOp;
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begin
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inherited Create;
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Assert(Assigned(AInitialScope));
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Assert(Assigned(AEvaluatorFactory));
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FInitialScope := AInitialScope;
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FEvaluatorFactory := AEvaluatorFactory;
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FCurrentDescriptor := AInitialScope.CreateDescriptor;
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FUpvalueStack := TObjectStack<TUpvalueMapping>.Create(True);
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FNestedLambdaCount := 0;
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FIsTailStack := TStack<Boolean>.Create;
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FNextIsTail := True;
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FBoxedDeclarations := nil;
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// Initialize operator folding maps
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FBinaryOperators := TDictionary<string, TScalar.TBinaryOp>.Create;
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for op := Low(TScalar.TBinaryOp) to High(TScalar.TBinaryOp) do
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FBinaryOperators.Add(op.ToString, op);
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FUnaryOperators := TDictionary<string, TScalar.TUnaryOp>.Create;
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FUnaryOperators.Add('not', TScalar.TUnaryOp.Not);
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// Note: '-' is handled as a special case in VisitFunctionCall
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end;
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destructor TAstBinder.Destroy;
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begin
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FUnaryOperators.Free;
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FBinaryOperators.Free;
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FIsTailStack.Free;
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FUpvalueStack.Free;
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FBoxedDeclarations.Free;
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inherited;
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end;
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function TAstBinder.Accept(const Node: IAstNode): TDataValue;
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begin
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if (not Assigned(Node)) or Done then
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exit;
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FIsTailStack.Push(FNextIsTail);
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try
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Result := inherited Accept(Node);
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finally
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FNextIsTail := FIsTailStack.Pop;
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end;
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end;
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procedure TAstBinder.EnterScope;
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begin
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FCurrentDescriptor := TScope.CreateDescriptor(FCurrentDescriptor);
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end;
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function TAstBinder.EvaluateAtCompileTime(const ANode: IAstNode): TDataValue;
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var
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subBinder: IAstBinder;
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subDescriptor: IScopeDescriptor;
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boundSubAst: IAstNode;
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evalScope: IExecutionScope;
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evaluator: IEvaluatorVisitor;
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tempInitScope: IExecutionScope;
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begin
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tempInitScope := TScope.CreateScope(FInitialScope.Parent, FCurrentDescriptor, nil);
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subBinder := TAstBinder.Create(tempInitScope, FEvaluatorFactory);
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boundSubAst := subBinder.Execute(ANode, subDescriptor);
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evalScope := subDescriptor.CreateScope(tempInitScope);
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evaluator := FEvaluatorFactory(evalScope);
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Result := evaluator.Execute(boundSubAst);
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end;
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function TAstBinder.Execute(const RootNode: IAstNode; out Descriptor: IScopeDescriptor): IAstNode;
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begin
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FBoxedDeclarations := TUpvalueAnalyzer.Analyze(RootNode, FCurrentDescriptor.Parent);
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try
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EnterScope;
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try
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var transformedValue := Accept(RootNode);
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if transformedValue.IsVoid then
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Result := TAst.Block([])
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else
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Result := transformedValue.AsIntf<IAstNode>;
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Descriptor := FCurrentDescriptor;
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finally
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ExitScope;
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end;
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finally
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// The binder now owns the hash set, which will be freed in the destructor.
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end;
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end;
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function TAstBinder.VisitMacroDefinition(const Node: IMacroDefinitionNode): TDataValue;
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begin
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FCurrentDescriptor.DefineMacro(Node.Name.Name, Node);
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Result := TDataValue.Void;
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end;
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function TAstBinder.VisitFunctionCall(const Node: IFunctionCallNode): TDataValue;
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var
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calleeIdentifier: TIdentifierNode;
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binaryOp: TScalar.TBinaryOp;
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unaryOp: TScalar.TUnaryOp;
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macroDef: IMacroDefinitionNode;
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begin
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// --- Optimization: Operator Folding ---
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if (Node.Callee is TIdentifierNode) then
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begin
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calleeIdentifier := Node.Callee as TIdentifierNode;
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// Try to fold binary operators
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if FBinaryOperators.TryGetValue(calleeIdentifier.Name, binaryOp) then
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begin
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if Length(Node.Arguments) = 2 then
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begin
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FNextIsTail := False;
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var left := Accept(Node.Arguments[0]).AsIntf<IAstNode>;
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var right := Accept(Node.Arguments[1]).AsIntf<IAstNode>;
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Result := TDataValue.FromIntf<IAstNode>(TAst.BinaryExpr(left, binaryOp, right));
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exit;
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end;
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end;
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// Try to fold unary operators
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if FUnaryOperators.TryGetValue(calleeIdentifier.Name, unaryOp) then
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begin
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if Length(Node.Arguments) = 1 then
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begin
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FNextIsTail := False;
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var right := Accept(Node.Arguments[0]).AsIntf<IAstNode>;
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Result := TDataValue.FromIntf<IAstNode>(TAst.UnaryExpr(unaryOp, right));
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exit;
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end;
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end;
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// Special case for negation '-'
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if (calleeIdentifier.Name = '-') and (Length(Node.Arguments) = 1) then
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begin
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FNextIsTail := False;
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var right := Accept(Node.Arguments[0]).AsIntf<IAstNode>;
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Result := TDataValue.FromIntf<IAstNode>(TAst.UnaryExpr(TScalar.TUnaryOp.Negate, right));
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exit;
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end;
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// --- Macro Expansion ---
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macroDef := FCurrentDescriptor.FindMacro(calleeIdentifier.Name);
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if macroDef <> nil then
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begin
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var expansionScope := TAst.CreateScope(nil);
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var params := macroDef.Parameters;
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if Length(Node.Arguments) <> Length(params) then
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raise Exception.CreateFmt(
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'Macro %s expects %d arguments, but got %d',
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[calleeIdentifier.Name, Length(params), Length(Node.Arguments)]);
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for var i := 0 to High(params) do
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expansionScope.Define(params[i].Name, TDataValue.FromIntf<IAstNode>(Node.Arguments[i]));
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if not (macroDef.Body is TQuasiquoteNode) then
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raise Exception.CreateFmt('Macro body for "%s" must be a quasiquoted expression.', [calleeIdentifier.Name]);
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var quasiquoteBody := macroDef.Body as TQuasiquoteNode;
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var expander := TExpansionVisitor.Create(Self, expansionScope);
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var expandedBody := expander.Execute(quasiquoteBody.Expression);
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var boundExpandedBody := Self.Accept(expandedBody).AsIntf<IAstNode>;
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var macroNode := TMacroExpansionNode.Create(Node, boundExpandedBody);
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Result := TDataValue.FromIntf<IMacroExpansionNode>(macroNode);
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exit;
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end;
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end;
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// --- Default: Bind as a standard function call ---
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var isTailCall := FIsTailStack.Peek;
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FNextIsTail := False;
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var callee := Accept(Node.Callee).AsIntf<IAstNode>;
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var args := TransformNodes<IAstNode>(Node.Arguments);
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var boundCall := TBoundFunctionCallNode.Create(Node, callee, args, isTailCall);
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Result := TDataValue.FromIntf<IFunctionCallNode>(boundCall);
|
|
end;
|
|
|
|
function TAstBinder.VisitMacroExpansionNode(const Node: IMacroExpansionNode): TDataValue;
|
|
var
|
|
boundCallee: IAstNode;
|
|
boundArgs: TArray<IAstNode>;
|
|
boundExpandedBody: IAstNode;
|
|
boundOriginalCall: IFunctionCallNode;
|
|
begin
|
|
boundCallee := Accept(Node.Callee).AsIntf<IAstNode>;
|
|
boundArgs := TransformNodes<IAstNode>(Node.Arguments);
|
|
boundExpandedBody := Accept(Node.ExpandedBody).AsIntf<IAstNode>;
|
|
boundOriginalCall := TAst.FunctionCall(boundCallee, boundArgs);
|
|
var newMacroNode := TMacroExpansionNode.Create(boundOriginalCall, boundExpandedBody);
|
|
Result := TDataValue.FromIntf<IMacroExpansionNode>(newMacroNode);
|
|
end;
|
|
|
|
procedure TAstBinder.ExitScope;
|
|
begin
|
|
FCurrentDescriptor := FCurrentDescriptor.Parent;
|
|
end;
|
|
|
|
function TAstBinder.IsValidIdentifier(const Name: string): Boolean;
|
|
var
|
|
c: Char;
|
|
begin
|
|
if Name.IsEmpty then
|
|
exit(False);
|
|
c := Name[1];
|
|
if not (c.IsLetter or (c = '_')) then
|
|
exit(False);
|
|
for c in Name do
|
|
begin
|
|
if not (c.IsLetterOrDigit or (c = '_') or (c = '-')) then
|
|
exit(False);
|
|
end;
|
|
Result := True;
|
|
end;
|
|
|
|
function TAstBinder.VisitAssignment(const Node: IAssignmentNode): TDataValue;
|
|
begin
|
|
FNextIsTail := False;
|
|
Result := inherited VisitAssignment(Node);
|
|
end;
|
|
|
|
function TAstBinder.VisitBinaryExpression(const Node: IBinaryExpressionNode): TDataValue;
|
|
begin
|
|
FNextIsTail := False;
|
|
Result := inherited VisitBinaryExpression(Node);
|
|
end;
|
|
|
|
function TAstBinder.VisitBlockExpression(const Node: IBlockExpressionNode): TDataValue;
|
|
var
|
|
exprs: TArray<IAstNode>;
|
|
i: Integer;
|
|
isContextTail: Boolean;
|
|
transformedValue: TDataValue;
|
|
exprList: TList<IAstNode>;
|
|
begin
|
|
isContextTail := FIsTailStack.Peek;
|
|
exprList := TList<IAstNode>.Create;
|
|
try
|
|
for i := 0 to High(Node.Expressions) do
|
|
begin
|
|
FNextIsTail := isContextTail and (i = High(Node.Expressions));
|
|
transformedValue := Accept(Node.Expressions[i]);
|
|
if not transformedValue.IsVoid then
|
|
exprList.Add(transformedValue.AsIntf<IAstNode>);
|
|
end;
|
|
exprs := exprList.ToArray;
|
|
finally
|
|
exprList.Free;
|
|
end;
|
|
|
|
if (Length(exprs) = Length(Node.Expressions)) then
|
|
begin
|
|
var same := True;
|
|
for i := 0 to High(exprs) do
|
|
if exprs[i] <> Node.Expressions[i] then
|
|
begin
|
|
same := False;
|
|
break;
|
|
end;
|
|
if same then
|
|
begin
|
|
Result := TDataValue.FromIntf<IBlockExpressionNode>(Node);
|
|
exit;
|
|
end;
|
|
end;
|
|
|
|
Result := TDataValue.FromIntf<IBlockExpressionNode>(TAst.Block(exprs));
|
|
end;
|
|
|
|
function TAstBinder.VisitIfExpression(const Node: IIfExpressionNode): TDataValue;
|
|
var
|
|
isContextTail: Boolean;
|
|
condition, thenBranch, elseBranch: IAstNode;
|
|
begin
|
|
isContextTail := FIsTailStack.Peek;
|
|
FNextIsTail := False;
|
|
condition := Accept(Node.Condition).AsIntf<IAstNode>;
|
|
FNextIsTail := isContextTail;
|
|
thenBranch := Accept(Node.ThenBranch).AsIntf<IAstNode>;
|
|
elseBranch := Accept(Node.ElseBranch).AsIntf<IAstNode>;
|
|
|
|
if (condition <> Node.Condition) or (thenBranch <> Node.ThenBranch) or (elseBranch <> Node.ElseBranch) then
|
|
Result := TDataValue.FromIntf<IIfExpressionNode>(TAst.IfExpr(condition, thenBranch, elseBranch))
|
|
else
|
|
Result := TDataValue.FromIntf<IIfExpressionNode>(Node);
|
|
end;
|
|
|
|
function TAstBinder.VisitLambdaExpression(const Node: ILambdaExpressionNode): TDataValue;
|
|
var
|
|
i: integer;
|
|
boundParams: TArray<IIdentifierNode>;
|
|
boundBody: IAstNode;
|
|
lambdaScope: IScopeDescriptor;
|
|
upvalues: TArray<TResolvedAddress>;
|
|
hasNestedLambdas: Boolean;
|
|
lastNestedLambdaCount: Integer;
|
|
boundLambda: ILambdaExpressionNode;
|
|
begin
|
|
FUpvalueStack.Push(TUpvalueMapping.Create);
|
|
try
|
|
EnterScope;
|
|
try
|
|
FCurrentDescriptor.Define('<self>');
|
|
SetLength(boundParams, Length(Node.Parameters));
|
|
for i := 0 to High(Node.Parameters) do
|
|
begin
|
|
var paramNode := Node.Parameters[i];
|
|
var slotIndex := FCurrentDescriptor.Define(paramNode.Name);
|
|
var address := TResolvedAddress.Create(akLocalOrParent, 0, slotIndex);
|
|
boundParams[i] := TBoundIdentifierNode.Create(paramNode, address);
|
|
end;
|
|
|
|
lastNestedLambdaCount := FNestedLambdaCount;
|
|
FNextIsTail := True;
|
|
boundBody := Accept(Node.Body).AsIntf<IAstNode>;
|
|
hasNestedLambdas := FNestedLambdaCount > lastNestedLambdaCount;
|
|
lambdaScope := FCurrentDescriptor;
|
|
finally
|
|
ExitScope;
|
|
end;
|
|
|
|
var upvalueMapping := FUpvalueStack.Peek;
|
|
var sortedPairs := upvalueMapping.Map.ToArray;
|
|
TArray.Sort<TPair<TResolvedAddress, Integer>>(
|
|
sortedPairs,
|
|
TComparer<TPair<TResolvedAddress, Integer>>.Construct(
|
|
function(const Left, Right: TPair<TResolvedAddress, Integer>): Integer begin Result := Left.Value - Right.Value; end
|
|
)
|
|
);
|
|
SetLength(upvalues, Length(sortedPairs));
|
|
for i := 0 to High(sortedPairs) do
|
|
upvalues[i] := sortedPairs[i].Key;
|
|
finally
|
|
FUpvalueStack.Pop;
|
|
end;
|
|
|
|
inc(FNestedLambdaCount);
|
|
boundLambda := TBoundLambdaExpressionNode.Create(Node, boundBody, boundParams, lambdaScope, upvalues, hasNestedLambdas);
|
|
Result := TDataValue.FromIntf<ILambdaExpressionNode>(boundLambda);
|
|
end;
|
|
|
|
function TAstBinder.VisitRecurNode(const Node: IRecurNode): TDataValue;
|
|
begin
|
|
if not FIsTailStack.Peek then
|
|
raise Exception.Create('''recur'' can only be used in a tail position.');
|
|
FNextIsTail := False;
|
|
Result := inherited VisitRecurNode(Node);
|
|
end;
|
|
|
|
function TAstBinder.VisitTernaryExpression(const Node: ITernaryExpressionNode): TDataValue;
|
|
var
|
|
isContextTail: Boolean;
|
|
condition, thenBranch, elseBranch: IAstNode;
|
|
begin
|
|
isContextTail := FIsTailStack.Peek;
|
|
FNextIsTail := False;
|
|
condition := Accept(Node.Condition).AsIntf<IAstNode>;
|
|
FNextIsTail := isContextTail;
|
|
thenBranch := Accept(Node.ThenBranch).AsIntf<IAstNode>;
|
|
elseBranch := Accept(Node.ElseBranch).AsIntf<IAstNode>;
|
|
|
|
if (condition <> Node.Condition) or (thenBranch <> Node.ThenBranch) or (elseBranch <> Node.ElseBranch) then
|
|
Result := TDataValue.FromIntf<ITernaryExpressionNode>(TAst.TernaryExpr(condition, thenBranch, elseBranch))
|
|
else
|
|
Result := TDataValue.FromIntf<ITernaryExpressionNode>(Node);
|
|
end;
|
|
|
|
function TAstBinder.VisitUnaryExpression(const Node: IUnaryExpressionNode): TDataValue;
|
|
begin
|
|
FNextIsTail := False;
|
|
Result := inherited VisitUnaryExpression(Node);
|
|
end;
|
|
|
|
function TAstBinder.VisitIdentifier(const Node: IIdentifierNode): TDataValue;
|
|
var
|
|
adr: TResolvedAddress;
|
|
boundNode: IIdentifierNode;
|
|
begin
|
|
adr := FCurrentDescriptor.FindSymbol(Node.Name);
|
|
if adr.Kind = akLocalOrParent then
|
|
begin
|
|
if (adr.ScopeDepth > 0) and (FUpvalueStack.Count > 0) then
|
|
begin
|
|
var upvalue := FUpvalueStack.Peek;
|
|
dec(adr.ScopeDepth);
|
|
var upvalueIndex: Integer;
|
|
if not upvalue.Map.TryGetValue(adr, upvalueIndex) then
|
|
begin
|
|
upvalueIndex := upvalue.Map.Count;
|
|
upvalue.Map.Add(adr, upvalueIndex);
|
|
end;
|
|
boundNode := TBoundIdentifierNode.Create(Node, TResolvedAddress.Create(akUpvalue, 0, upvalueIndex));
|
|
end
|
|
else
|
|
boundNode := TBoundIdentifierNode.Create(Node, adr);
|
|
Result := TDataValue.FromIntf<IIdentifierNode>(boundNode);
|
|
end
|
|
else
|
|
raise Exception.CreateFmt('Undefined identifier: "%s"', [Node.Name]);
|
|
end;
|
|
|
|
function TAstBinder.VisitVariableDeclaration(const Node: IVariableDeclarationNode): TDataValue;
|
|
var
|
|
initializer: IAstNode;
|
|
slotIndex: Integer;
|
|
address: TResolvedAddress;
|
|
boundIdentifier: IIdentifierNode;
|
|
isBoxed: Boolean;
|
|
boundDecl: IVariableDeclarationNode;
|
|
begin
|
|
if not IsValidIdentifier(Node.Identifier.Name) then
|
|
raise Exception.CreateFmt('Invalid identifier name: "%s".', [Node.Identifier.Name]);
|
|
|
|
FNextIsTail := False;
|
|
initializer := nil;
|
|
if Node.Initializer <> nil then
|
|
initializer := Accept(Node.Initializer).AsIntf<IAstNode>;
|
|
|
|
slotIndex := FCurrentDescriptor.Define(Node.Identifier.Name);
|
|
address := TResolvedAddress.Create(akLocalOrParent, 0, slotIndex);
|
|
boundIdentifier := TBoundIdentifierNode.Create(Node.Identifier, address);
|
|
isBoxed := (FBoxedDeclarations <> nil) and FBoxedDeclarations.Contains(Node);
|
|
boundDecl := TBoundVariableDeclarationNode.Create(boundIdentifier, initializer, isBoxed);
|
|
Result := TDataValue.FromIntf<IVariableDeclarationNode>(boundDecl);
|
|
end;
|
|
|
|
end.
|