defer and struct hooks

This commit is contained in:
nub31
2025-09-19 23:08:12 +02:00
parent 9167660dfc
commit c9064f0a43
15 changed files with 240 additions and 97 deletions

View File

@@ -16,11 +16,14 @@ public class QBEGenerator
private readonly List<StringLiteral> _stringLiterals = [];
private readonly Stack<string> _breakLabels = [];
private readonly Stack<string> _continueLabels = [];
private readonly Stack<Scope> _scopes = new();
private int _tmpIndex;
private int _labelIndex;
private int _cStringLiteralIndex;
private int _stringLiteralIndex;
private Scope Scope => _scopes.Peek();
public QBEGenerator(List<DefinitionNode> definitions, HashSet<StructTypeNode> structTypes)
{
_definitions = definitions;
@@ -34,6 +37,7 @@ public class QBEGenerator
_stringLiterals.Clear();
_breakLabels.Clear();
_continueLabels.Clear();
_scopes.Clear();
_tmpIndex = 0;
_labelIndex = 0;
_cStringLiteralIndex = 0;
@@ -307,6 +311,16 @@ public class QBEGenerator
{
var value = EmitExpression(source);
_writer.Indented($"blit {value}, {destination}, {SizeOf(source.Type)}");
if (source.Type is StructTypeNode structType)
{
var copyFunc = structType.Functions.FirstOrDefault(x => x.Hook == "oncopy");
if (copyFunc != null)
{
_writer.Indented($"call {StructFuncName(structType.Module, structType.Name, copyFunc.Name)}(l {destination})");
}
}
return;
}
@@ -349,48 +363,6 @@ public class QBEGenerator
}
}
private string EmitCopy(ExpressionNode source)
{
if (source is RValueExpressionNode || source.Type.IsScalar)
{
return EmitExpression(source);
}
var value = EmitExpression(source);
var destination = TmpName();
if (source.Type.IsValueType)
{
var size = SizeOf(source.Type);
_writer.Indented($"{destination} =l alloc8 {size}");
_writer.Indented($"blit {value}, {destination}, {size}");
return destination;
}
switch (source.Type)
{
case ArrayTypeNode arrayType:
var arraySize = EmitArraySizeInBytes(arrayType, value);
_writer.Indented($"{destination} =l alloc8 {arraySize}");
EmitMemcpy(value, destination, arraySize);
break;
case CStringTypeNode:
var cstrSize = EmitCStringSizeInBytes(value);
_writer.Indented($"{destination} =l alloc8 {cstrSize}");
EmitMemcpy(value, destination, cstrSize);
break;
case StringTypeNode:
var strSize = EmitStringSizeInBytes(value);
_writer.Indented($"{destination} =l alloc8 {strSize}");
EmitMemcpy(value, destination, strSize);
break;
default:
throw new InvalidOperationException($"Cannot copy type {source.Type}");
}
return destination;
}
private void EmitStructType(StructTypeNode structType)
{
// todo(nub31): qbe expects structs to be declared in order. We must Check the dependencies of the struct to see if a type need to be declared before this one
@@ -450,7 +422,13 @@ public class QBEGenerator
_writer.WriteLine(") {");
_writer.WriteLine("@start");
EmitBlock(function.Body);
var scope = new Scope();
foreach (var parameter in function.Signature.Parameters)
{
scope.Variables.Push(new Variable(parameter.Name, parameter.Type));
}
EmitBlock(function.Body, scope);
// Implicit return for void functions if no explicit return has been set
if (function.Signature.ReturnType is VoidTypeNode && function.Body.Statements.LastOrDefault() is not ReturnNode)
@@ -488,18 +466,31 @@ public class QBEGenerator
_writer.WriteLine(") {");
_writer.WriteLine("@start");
EmitBlock(funcDef.Body);
var scope = new Scope();
foreach (var parameter in funcDef.Signature.Parameters)
{
scope.Variables.Push(new Variable(parameter.Name, parameter.Type));
}
EmitBlock(funcDef.Body, scope);
_writer.WriteLine("}");
_writer.NewLine();
}
private void EmitBlock(BlockNode block)
private void EmitBlock(BlockNode block, Scope? scope = null)
{
scope ??= Scope.SubScope();
_scopes.Push(scope);
foreach (var statement in block.Statements)
{
EmitStatement(statement);
}
EmitScopeCleanup();
_scopes.Pop();
}
private void EmitStatement(StatementNode statement)
@@ -510,9 +501,11 @@ public class QBEGenerator
EmitCopyInto(assignment.Value, EmitAddressOf(assignment.Target));
break;
case BreakNode:
EmitScopeCleanup();
_writer.Indented($"jmp {_breakLabels.Peek()}");
break;
case ContinueNode:
EmitScopeCleanup();
_writer.Indented($"jmp {_continueLabels.Peek()}");
break;
case IfNode ifStatement:
@@ -527,6 +520,9 @@ public class QBEGenerator
case VariableDeclarationNode variableDeclaration:
EmitVariableDeclaration(variableDeclaration);
break;
case DeferNode defer:
Scope.DeferredStatements.Push(defer.Statement);
break;
case WhileNode whileStatement:
EmitWhile(whileStatement);
break;
@@ -538,6 +534,26 @@ public class QBEGenerator
}
}
private void EmitScopeCleanup()
{
while (Scope.DeferredStatements.TryPop(out var deferredStatement))
{
EmitStatement(deferredStatement);
}
while (Scope.Variables.TryPop(out var variable))
{
if (variable.Type is StructTypeNode structType)
{
var destroyFunc = structType.Functions.FirstOrDefault(x => x.Hook == "ondestroy");
if (destroyFunc != null)
{
_writer.Indented($"call {StructFuncName(structType.Module, structType.Name, destroyFunc.Name)}(l %{variable.Name})");
}
}
}
}
private void EmitIf(IfNode ifStatement)
{
var trueLabel = LabelName();
@@ -552,7 +568,7 @@ public class QBEGenerator
_writer.WriteLine(falseLabel);
if (ifStatement.Else.HasValue)
{
ifStatement.Else.Value.Match(EmitIf, EmitBlock);
ifStatement.Else.Value.Match(EmitIf, b => EmitBlock(b));
}
_writer.WriteLine(endLabel);
@@ -563,10 +579,12 @@ public class QBEGenerator
if (@return.Value.HasValue)
{
var result = EmitExpression(@return.Value.Value);
EmitScopeCleanup();
_writer.Indented($"ret {result}");
}
else
{
EmitScopeCleanup();
_writer.Indented("ret");
}
}
@@ -580,6 +598,8 @@ public class QBEGenerator
{
EmitCopyInto(variableDeclaration.Assignment.Value, name);
}
Scope.Variables.Push(new Variable(variableDeclaration.Name, variableDeclaration.Type));
}
private void EmitWhile(WhileNode whileStatement)
@@ -677,7 +697,6 @@ public class QBEGenerator
BinaryExpressionNode expr => EmitBinaryExpression(expr),
ConvertFloatNode expr => EmitConvertFloat(expr),
ConvertIntNode expr => EmitConvertInt(expr),
DereferenceNode expr => EmitLoad(expr.Type, EmitExpression(expr.Expression)),
FuncCallNode expr => EmitFuncCall(expr),
FuncIdentifierNode expr => FuncName(expr.Module, expr.Name, expr.ExternSymbol),
FuncParameterIdentifierNode expr => $"%{expr.Name}",
@@ -740,6 +759,7 @@ public class QBEGenerator
return lval switch
{
ArrayIndexAccessNode arrayIndexAccess => EmitAddressOfArrayIndexAccess(arrayIndexAccess),
DereferenceNode dereference => EmitExpression(dereference.Expression),
StructFieldAccessNode structFieldAccess => EmitAddressOfStructFieldAccess(structFieldAccess),
VariableIdentifierNode variableIdent => $"%{variableIdent.Name}",
_ => throw new ArgumentOutOfRangeException(nameof(lval))
@@ -948,6 +968,12 @@ public class QBEGenerator
_writer.Indented($"{destination} =l alloc8 {size}");
_writer.Indented($"call {StructCtorName(structInitializer.StructType.Module, structInitializer.StructType.Name)}(l {destination})");
var createFunc = structInitializer.StructType.Functions.FirstOrDefault(x => x.Hook == "oncreate");
if (createFunc != null)
{
_writer.Indented($"call {StructFuncName(structInitializer.StructType.Module, structInitializer.StructType.Name, createFunc.Name)}(l {destination})");
}
foreach (var (field, value) in structInitializer.Initializers)
{
var offset = TmpName();
@@ -1015,8 +1041,18 @@ public class QBEGenerator
foreach (var parameter in structFuncCall.Parameters)
{
var copy = EmitCopy(parameter);
parameterStrings.Add($"{FuncQBETypeName(parameter.Type)} {copy}");
var value = EmitExpression(parameter);
if (parameter.Type is StructTypeNode structType)
{
var copyFunc = structType.Functions.FirstOrDefault(x => x.Hook == "oncopy");
if (copyFunc != null)
{
_writer.Indented($"call {StructFuncName(structType.Module, structType.Name, copyFunc.Name)}(l {value})");
}
}
parameterStrings.Add($"{FuncQBETypeName(parameter.Type)} {value}");
}
if (structFuncCall.Type is VoidTypeNode)
@@ -1093,8 +1129,18 @@ public class QBEGenerator
foreach (var parameter in funcCall.Parameters)
{
var copy = EmitCopy(parameter);
parameterStrings.Add($"{FuncQBETypeName(parameter.Type)} {copy}");
var value = EmitExpression(parameter);
if (parameter.Type is StructTypeNode structType)
{
var copyFunc = structType.Functions.FirstOrDefault(x => x.Hook == "oncopy");
if (copyFunc != null)
{
_writer.Indented($"call {StructFuncName(structType.Module, structType.Name, copyFunc.Name)}(l {value})");
}
}
parameterStrings.Add($"{FuncQBETypeName(parameter.Type)} {value}");
}
if (funcCall.Type is VoidTypeNode)
@@ -1242,6 +1288,20 @@ public class QBEGenerator
}
}
// todo(nub31): Parent is not used when getting variables and deferred statements
public class Scope(Scope? parent = null)
{
public readonly Stack<StatementNode> DeferredStatements = [];
public readonly Stack<Variable> Variables = [];
public Scope SubScope()
{
return new Scope(this);
}
}
public record Variable(string Name, TypeNode Type);
public class StringLiteral(string value, string name)
{
public string Value { get; } = value;

View File

@@ -32,7 +32,7 @@ public record ModuleStructField(string Name, TypeSyntax Type, bool HasDefaultVal
public record ModuleStructFunctionParameter(string Name, TypeSyntax Type);
public record ModuleStructFunction(string Name, List<ModuleStructFunctionParameter> Parameters, TypeSyntax ReturnType);
public record ModuleStructFunction(string Name, string? Hook, List<ModuleStructFunctionParameter> Parameters, TypeSyntax ReturnType);
public record ModuleStruct(bool Exported, string Name, List<ModuleStructField> Fields, List<ModuleStructFunction> Functions);

View File

@@ -36,7 +36,7 @@ public class ModuleRepository
foreach (var function in structDef.Functions)
{
var parameters = function.Signature.Parameters.Select(x => new ModuleStructFunctionParameter(x.Name, x.Type)).ToList();
functions.AddRange(new ModuleStructFunction(function.Name, parameters, function.Signature.ReturnType));
functions.AddRange(new ModuleStructFunction(function.Name, function.Hook, parameters, function.Signature.ReturnType));
}
module.RegisterStruct(structDef.Exported, structDef.Name, fields, functions);

View File

@@ -175,13 +175,19 @@ public sealed class Parser
{
var memberStartIndex = _tokenIndex;
string? hook = null;
if (TryExpectSymbol(Symbol.At))
{
hook = ExpectIdentifier().Value;
}
if (TryExpectSymbol(Symbol.Func))
{
var funcName = ExpectIdentifier().Value;
var funcSignature = ParseFuncSignature();
var funcBody = ParseBlock();
funcs.Add(new StructFuncSyntax(GetTokens(memberStartIndex), funcName, funcSignature, funcBody));
funcs.Add(new StructFuncSyntax(GetTokens(memberStartIndex), funcName, hook, funcSignature, funcBody));
}
else
{
@@ -209,6 +215,8 @@ public sealed class Parser
{
switch (symbol.Symbol)
{
case Symbol.OpenBrace:
return ParseBlock();
case Symbol.Return:
return ParseReturn();
case Symbol.If:
@@ -219,6 +227,8 @@ public sealed class Parser
return ParseFor();
case Symbol.Let:
return ParseVariableDeclaration();
case Symbol.Defer:
return ParseDefer();
case Symbol.Break:
return ParseBreak();
case Symbol.Continue:
@@ -264,14 +274,22 @@ public sealed class Parser
return new VariableDeclarationSyntax(GetTokens(startIndex), name, explicitType, assignment);
}
private StatementSyntax ParseBreak()
private DeferSyntax ParseDefer()
{
var startIndex = _tokenIndex;
ExpectSymbol(Symbol.Defer);
var statement = ParseStatement();
return new DeferSyntax(GetTokens(startIndex), statement);
}
private BreakSyntax ParseBreak()
{
var startIndex = _tokenIndex;
ExpectSymbol(Symbol.Break);
return new BreakSyntax(GetTokens(startIndex));
}
private StatementSyntax ParseContinue()
private ContinueSyntax ParseContinue()
{
var startIndex = _tokenIndex;
ExpectSymbol(Symbol.Continue);
@@ -303,9 +321,14 @@ public sealed class Parser
var elseStatement = Optional<Variant<IfSyntax, BlockSyntax>>.Empty();
if (TryExpectSymbol(Symbol.Else))
{
elseStatement = TryExpectSymbol(Symbol.If)
? (Variant<IfSyntax, BlockSyntax>)ParseIf()
: (Variant<IfSyntax, BlockSyntax>)ParseBlock();
if (CurrentToken is SymbolToken { Symbol: Symbol.If })
{
elseStatement = (Variant<IfSyntax, BlockSyntax>)ParseIf();
}
else
{
elseStatement = (Variant<IfSyntax, BlockSyntax>)ParseBlock();
}
}
return new IfSyntax(GetTokens(startIndex), condition, body, elseStatement);

View File

@@ -12,6 +12,6 @@ public record FuncSyntax(IEnumerable<Token> Tokens, string Name, bool Exported,
public record StructFieldSyntax(IEnumerable<Token> Tokens, string Name, TypeSyntax Type, Optional<ExpressionSyntax> Value) : SyntaxNode(Tokens);
public record StructFuncSyntax(IEnumerable<Token> Tokens, string Name, FuncSignatureSyntax Signature, BlockSyntax Body) : SyntaxNode(Tokens);
public record StructFuncSyntax(IEnumerable<Token> Tokens, string Name, string? Hook, FuncSignatureSyntax Signature, BlockSyntax Body) : SyntaxNode(Tokens);
public record StructSyntax(IEnumerable<Token> Tokens, string Name, bool Exported, List<StructFieldSyntax> Fields, List<StructFuncSyntax> Functions) : DefinitionSyntax(Tokens, Name, Exported);

View File

@@ -4,6 +4,8 @@ namespace NubLang.Parsing.Syntax;
public abstract record StatementSyntax(IEnumerable<Token> Tokens) : SyntaxNode(Tokens);
public record BlockSyntax(IEnumerable<Token> Tokens, List<StatementSyntax> Statements) : StatementSyntax(Tokens);
public record StatementExpressionSyntax(IEnumerable<Token> Tokens, ExpressionSyntax Expression) : StatementSyntax(Tokens);
public record ReturnSyntax(IEnumerable<Token> Tokens, Optional<ExpressionSyntax> Value) : StatementSyntax(Tokens);
@@ -18,6 +20,8 @@ public record ContinueSyntax(IEnumerable<Token> Tokens) : StatementSyntax(Tokens
public record BreakSyntax(IEnumerable<Token> Tokens) : StatementSyntax(Tokens);
public record DeferSyntax(IEnumerable<Token> Tokens, StatementSyntax Statement) : StatementSyntax(Tokens);
public record WhileSyntax(IEnumerable<Token> Tokens, ExpressionSyntax Condition, BlockSyntax Body) : StatementSyntax(Tokens);
public record ForSyntax(IEnumerable<Token> Tokens, string ElementIdent, string? IndexIdent, ExpressionSyntax Target, BlockSyntax Body) : StatementSyntax(Tokens);

View File

@@ -6,6 +6,4 @@ public abstract record SyntaxNode(IEnumerable<Token> Tokens);
public record SyntaxTreeMetadata(string ModuleName, List<string> Imports);
public record SyntaxTree(List<DefinitionSyntax> Definitions, SyntaxTreeMetadata Metadata);
public record BlockSyntax(IEnumerable<Token> Tokens, List<StatementSyntax> Statements) : SyntaxNode(Tokens);
public record SyntaxTree(List<DefinitionSyntax> Definitions, SyntaxTreeMetadata Metadata);

View File

@@ -80,4 +80,6 @@ public enum Symbol
Module,
Import,
Export,
Defer,
At,
}

View File

@@ -23,6 +23,7 @@ public sealed class Tokenizer
["module"] = Symbol.Module,
["export"] = Symbol.Export,
["import"] = Symbol.Import,
["defer"] = Symbol.Defer,
};
private static readonly Dictionary<char[], Symbol> Symbols = new()
@@ -58,6 +59,7 @@ public sealed class Tokenizer
[[';']] = Symbol.Semi,
[['%']] = Symbol.Percent,
[['|']] = Symbol.Pipe,
[['@']] = Symbol.At,
};
private static readonly (char[] Pattern, Symbol Symbol)[] OrderedSymbols = Symbols

View File

@@ -72,7 +72,7 @@ public record StructFieldAccessNode(TypeNode Type, StructTypeNode StructType, Ex
public record StructInitializerNode(StructTypeNode StructType, Dictionary<string, ExpressionNode> Initializers) : RValueExpressionNode(StructType);
public record DereferenceNode(TypeNode Type, ExpressionNode Expression) : RValueExpressionNode(Type);
public record DereferenceNode(TypeNode Type, ExpressionNode Expression) : LValueExpressionNode(Type);
public record ConvertIntNode(TypeNode Type, ExpressionNode Value, IntTypeNode ValueType, IntTypeNode TargetType) : RValueExpressionNode(Type);

View File

@@ -1,5 +1,3 @@
namespace NubLang.TypeChecking.Node;
public abstract record Node;
public record BlockNode(List<StatementNode> Statements) : Node;
public abstract record Node;

View File

@@ -2,9 +2,13 @@
public abstract record StatementNode : Node;
public abstract record TerminalStatementNode : StatementNode;
public record BlockNode(List<StatementNode> Statements) : StatementNode;
public record StatementExpressionNode(ExpressionNode Expression) : StatementNode;
public record ReturnNode(Optional<ExpressionNode> Value) : StatementNode;
public record ReturnNode(Optional<ExpressionNode> Value) : TerminalStatementNode;
public record AssignmentNode(LValueExpressionNode Target, ExpressionNode Value) : StatementNode;
@@ -12,9 +16,11 @@ public record IfNode(ExpressionNode Condition, BlockNode Body, Optional<Variant<
public record VariableDeclarationNode(string Name, Optional<ExpressionNode> Assignment, TypeNode Type) : StatementNode;
public record ContinueNode : StatementNode;
public record ContinueNode : TerminalStatementNode;
public record BreakNode : StatementNode;
public record BreakNode : TerminalStatementNode;
public record DeferNode(StatementNode Statement) : StatementNode;
public record WhileNode(ExpressionNode Condition, BlockNode Body) : StatementNode;

View File

@@ -119,9 +119,10 @@ public class StructTypeField(string name, TypeNode type, bool hasDefaultValue)
public bool HasDefaultValue { get; } = hasDefaultValue;
}
public class StructTypeFunc(string name, FuncTypeNode type)
public class StructTypeFunc(string name, string? hook, FuncTypeNode type)
{
public string Name { get; } = name;
public string? Hook { get; set; } = hook;
public FuncTypeNode Type { get; } = type;
}

View File

@@ -73,7 +73,7 @@ public sealed class TypeChecker
{
var parameters = function.Signature.Parameters.Select(x => ResolveType(x.Type)).ToList();
var funcType = new FuncTypeNode(parameters, ResolveType(function.Signature.ReturnType));
functionTypes.Add(new StructTypeFunc(function.Name, funcType));
functionTypes.Add(new StructTypeFunc(function.Name, function.Hook, funcType));
}
var type = new StructTypeNode(_syntaxTree.Metadata.ModuleName, node.Name, fieldTypes, functionTypes);
@@ -127,10 +127,19 @@ public sealed class TypeChecker
body = CheckBlock(node.Body, scope);
// Insert implicit return for void functions
if (signature.ReturnType is VoidTypeNode && body.Statements.LastOrDefault() is not ReturnNode)
if (!AlwaysReturns(body))
{
body.Statements.Add(new ReturnNode(Optional<ExpressionNode>.Empty()));
if (signature.ReturnType is VoidTypeNode)
{
body.Statements.Add(new ReturnNode(Optional<ExpressionNode>.Empty()));
}
else
{
Diagnostics.Add(Diagnostic
.Error("Not all code paths return a value")
.At(node.Body.Tokens.LastOrDefault())
.Build());
}
}
_funcReturnTypes.Pop();
@@ -150,6 +159,7 @@ public sealed class TypeChecker
ReturnSyntax statement => CheckReturn(statement),
StatementExpressionSyntax statement => CheckStatementExpression(statement),
VariableDeclarationSyntax statement => CheckVariableDeclaration(statement),
DeferSyntax statement => CheckDefer(statement),
WhileSyntax statement => CheckWhile(statement),
ForSyntax statement => CheckFor(statement),
_ => throw new ArgumentOutOfRangeException(nameof(node))
@@ -224,6 +234,11 @@ public sealed class TypeChecker
return new VariableDeclarationNode(statement.Name, Optional.OfNullable(assignmentNode), type);
}
private DeferNode CheckDefer(DeferSyntax statement)
{
return new DeferNode(CheckStatement(statement.Statement));
}
private WhileNode CheckWhile(WhileSyntax statement)
{
var condition = CheckExpression(statement.Condition, new BoolTypeNode());
@@ -734,8 +749,8 @@ public sealed class TypeChecker
if (missingFields.Length != 0)
{
throw new TypeCheckerException(Diagnostic
.Error($"Fields {string.Join(", ", missingFields)} are not initialized")
Diagnostics.Add(Diagnostic
.Warning($"Fields {string.Join(", ", missingFields)} are not initialized")
.At(expression)
.Build());
}
@@ -759,7 +774,7 @@ public sealed class TypeChecker
if (reachable)
{
statements.Add(checkedStatement);
if (checkedStatement is ReturnNode or BreakNode or ContinueNode)
if (checkedStatement is TerminalStatementNode)
{
reachable = false;
}
@@ -779,6 +794,17 @@ public sealed class TypeChecker
return new BlockNode(statements);
}
private bool AlwaysReturns(StatementNode statement)
{
return statement switch
{
ReturnNode => true,
BlockNode block => block.Statements.Count != 0 && AlwaysReturns(block.Statements.Last()),
IfNode ifNode => AlwaysReturns(ifNode.Body) && ifNode.Else.TryGetValue(out var elseStatement) ? elseStatement.Match(AlwaysReturns, AlwaysReturns) : true,
_ => false
};
}
private TypeNode ResolveType(TypeSyntax type)
{
return type switch
@@ -838,7 +864,7 @@ public sealed class TypeChecker
{
var parameters = function.Parameters.Select(x => ResolveType(x.Type)).ToList();
var type = new FuncTypeNode(parameters, ResolveType(function.ReturnType));
result.Functions.Add(new StructTypeFunc(function.Name, type));
result.Functions.Add(new StructTypeFunc(function.Name, function.Hook, type));
}
ReferencedStructTypes.Add(result);

View File

@@ -1,6 +1,8 @@
module "main"
extern "puts" func puts(text: cstring)
extern "malloc" func malloc(size: u64): ^u64
extern "free" func free(address: ^u64)
struct Human
{
@@ -9,28 +11,49 @@ struct Human
extern "main" func main(args: []cstring): i64
{
let x = [2]cstring
let x: ref = {}
x[0] = "test1"
x[1] = "test2"
for u in x
{
puts(u)
}
let me: Human = {
name = "test"
}
puts(me.name)
test(32)
test(x)
return 0
}
func test(x: u8)
func test(x: ref)
{
}
struct ref
{
value: ^u64
count: ^u64
@oncreate
func on_create()
{
puts("on_create")
this.value = malloc(8)
this.count = malloc(8)
this.count^ = 1
}
@oncopy
func on_copy()
{
puts("on_copy")
this.count^ = this.count^ + 1
}
@ondestroy
func on_destroy()
{
puts("on_destroy")
this.count^ = this.count^ - 1
if this.count^ <= 0
{
puts("free")
free(this.value)
free(this.count)
}
}
}