public override AstNode VisitMainClass(MainClass ast)
{
//main class must be the first class.
Debug.Assert(m_types.Count == 0);
var name = ast.Name.Value;
var mainclassType = new CodeClassType() { Name = name, IsStatic = true };
m_types.Add(mainclassType);
ast.Type = mainclassType;
return ast;
}
public override AstNode VisitClassDecl(ClassDecl ast)
{
var name = ast.Name.Value;
if (m_types.Contains(name))
{
m_errorManager.AddError(c_SE_TypeNameDuplicates, ast.Name.Span, name);
return ast;
}
var classType = new CodeClassType() { Name = name };
m_types.Add(classType);
ast.Type = classType;
return ast;
}
public override AstNode VisitClassDecl(ClassDecl ast)
{
var name = ast.Name.Content;
if (m_types.Contains(name))
{
AddError(c_SE_TypeNameDuplicates, ast.Name.Span, name);
return(ast);
}
var classType = new CodeClassType()
{
Name = name
};
m_types.Add(classType);
ast.Type = classType;
return(ast);
}
public override AstNode VisitMainClass(MainClass ast)
{
m_currentType = ast.Type as CodeClassType;
Debug.Assert(m_currentType.Methods.Count == 0);
Debug.Assert(m_currentType.StaticMethods.Count == 1);
m_currentMethod = m_currentType.StaticMethods[0];
m_currentVariableIndex = 0;
m_currentMethodParameters = new VariableCollection <Parameter>()
{
new Parameter()
{
Name = ast.ArgName.Content, Type = ArrayType.StrArray
}
};
m_currentMethodVariables = new VariableCollection <VariableInfo>();
foreach (var statement in ast.Statements)
{
Visit(statement);
}
return(ast);
}
private void ResolveMethod(Call ast, CodeClassType targetType)
{
if (targetType == null)
{
AddError(c_SE_MethodMissing, ast.Method.MethodName.Span, ast.Method.MethodName.Content);
ast.ExpressionType = PrimaryType.Unknown;
return;
}
// step 1: collect candidates from current type
var candidates = (from m in targetType.Methods
where String.Equals(m.Name, ast.Method.MethodName.Content, StringComparison.InvariantCulture) &&
m.Parameters.Count == ast.Arguments.Count
select m).ToArray();
if (candidates.Length == 0)
{
ResolveMethod(ast, targetType.BaseType);
return;
}
// step 2: remove unqualifed candidates
List <Method> qualifiedCandidates = new List <Method>();
foreach (var candidate in candidates)
{
bool isQualified = true;
for (int i = 0; i < candidate.Parameters.Count; i++)
{
if (!candidate.Parameters[i].Type.IsAssignableFrom(ast.Arguments[i].ExpressionType))
{
isQualified = false;
break;
}
}
if (isQualified)
{
qualifiedCandidates.Add(candidate);
}
}
if (qualifiedCandidates.Count == 0)
{
ResolveMethod(ast, targetType.BaseType);
return;
}
// step 3: choose a "best" one
if (qualifiedCandidates.Count > 1)
{
var comparer = new MethodOverloadingComparer(ast.Arguments);
qualifiedCandidates.Sort(comparer);
var firstCandidate = qualifiedCandidates[0];
var secondCandidate = qualifiedCandidates[1];
if (comparer.Compare(firstCandidate, secondCandidate) < 0)
{
//choose first as the best one
ast.Method.MethodInfo = firstCandidate;
ast.ExpressionType = firstCandidate.ReturnType;
}
else
{
//ambiguous between first & second
AddError(c_SE_MethodAmbiguous, ast.Method.MethodName.Span,
firstCandidate.GetSignatureString(), secondCandidate.GetSignatureString());
ast.ExpressionType = PrimaryType.Unknown;
}
}
else
{
ast.Method.MethodInfo = qualifiedCandidates[0];
ast.ExpressionType = qualifiedCandidates[0].ReturnType;
}
}
private void ResolveMethod(Call ast, CodeClassType targetType)
{
if (targetType == null)
{
m_errorManager.AddError(c_SE_MethodMissing, ast.Method.MethodName.Span, ast.Method.MethodName.Value);
ast.ExpressionType = PrimaryType.Unknown;
return;
}
// step 1: collect candidates from current type
var candidates = (from m in targetType.Methods
where String.Equals(m.Name, ast.Method.MethodName.Value, StringComparison.InvariantCulture)
&& m.Parameters.Count == ast.Arguments.Count
select m).ToArray();
if (candidates.Length == 0)
{
ResolveMethod(ast, targetType.BaseType);
return;
}
// step 2: remove unqualifed candidates
List<Method> qualifiedCandidates = new List<Method>();
foreach (var candidate in candidates)
{
bool isQualified = true;
for (int i = 0; i < candidate.Parameters.Count; i++)
{
if (!candidate.Parameters[i].Type.IsAssignableFrom(ast.Arguments[i].ExpressionType))
{
isQualified = false;
break;
}
}
if (isQualified) qualifiedCandidates.Add(candidate);
}
if (qualifiedCandidates.Count == 0)
{
ResolveMethod(ast, targetType.BaseType);
return;
}
// step 3: choose a "best" one
if (qualifiedCandidates.Count > 1)
{
var comparer = new MethodOverloadingComparer(ast.Arguments);
qualifiedCandidates.Sort(comparer);
var firstCandidate = qualifiedCandidates[0];
var secondCandidate = qualifiedCandidates[1];
if (comparer.Compare(firstCandidate, secondCandidate) < 0)
{
//choose first as the best one
ast.Method.MethodInfo = firstCandidate;
ast.ExpressionType = firstCandidate.ReturnType;
}
else
{
//ambiguous between first & second
m_errorManager.AddError(c_SE_MethodAmbiguous, ast.Method.MethodName.Span,
firstCandidate.GetSignatureString(), secondCandidate.GetSignatureString());
ast.ExpressionType = PrimaryType.Unknown;
}
}
else
{
ast.Method.MethodInfo = qualifiedCandidates[0];
ast.ExpressionType = qualifiedCandidates[0].ReturnType;
}
}
private VariableInfo ResolveField(CodeClassType type, Lexeme identifier)
{
//step1, see current class
if (type.Fields.Contains(identifier.Value))
{
return type.Fields[identifier.Value];
}
//step2, see base class
if (m_currentType.BaseType != null)
{
return ResolveField(m_currentType.BaseType, identifier);
}
m_errorManager.AddError(c_SE_VariableDeclMissing, identifier.Span, identifier.Value);
return null;
}
public override AstNode VisitMainClass(MainClass ast)
{
m_currentType = ast.Type as CodeClassType;
Debug.Assert(m_currentType.Methods.Count == 0);
Debug.Assert(m_currentType.StaticMethods.Count == 1);
m_currentMethod = m_currentType.StaticMethods[0];
m_currentVariableIndex = 0;
m_currentMethodParameters = new VariableCollection<Parameter>() { new Parameter() { Name = ast.ArgName.Value, Type = ArrayType.StrArray } };
m_currentMethodVariables = new VariableCollection<VariableInfo>();
foreach (var statement in ast.Statements)
{
Visit(statement);
}
return ast;
}
public override AstNode VisitClassDecl(ClassDecl ast)
{
m_currentType = ast.Type as CodeClassType;
foreach (var method in ast.Methods)
{
Visit(method);
}
return ast;
}
