static CodeTypeDeclaration CreateAstVisitorInterface(List<Type> nodeTypes)
{
EasyTypeDeclaration td = new EasyTypeDeclaration("IAstVisitor");
td.IsInterface = true;
foreach (Type t in nodeTypes) {
if (!t.IsAbstract) {
EasyMethod m = td.AddMethod(typeof(object), VisitPrefix + t.Name);
m.AddParameter(ConvertType(t), GetFieldName(t.Name));
m.AddParameter(typeof(object), "data");
}
}
return td;
}
static CodeTypeDeclaration CreateNodeTrackingAstVisitorClass(List<Type> nodeTypes)
{
EasyTypeDeclaration td = new EasyTypeDeclaration("NodeTrackingAstVisitor");
td.TypeAttributes = TypeAttributes.Public | TypeAttributes.Class | TypeAttributes.Abstract;
td.BaseTypes.Add(new CodeTypeReference("AbstractAstVisitor"));
string comment = "<summary>\n " +
"The NodeTrackingAstVisitor will iterate through the whole AST,\n " +
"just like the AbstractAstVisitor, and calls the virtual methods\n " +
"BeginVisit and EndVisit for each node being visited.\n " +
"</summary>";
td.Comments.Add(new CodeCommentStatement(comment, true));
comment = "<remarks>\n " +
"base.Visit(node, data) calls this.TrackedVisit(node, data), so if\n " +
"you want to visit child nodes using the default visiting behaviour,\n " +
"use base.TrackedVisit(parentNode, data).\n " +
"</remarks>";
td.Comments.Add(new CodeCommentStatement(comment, true));
EasyMethod m = td.AddMethod("BeginVisit");
m.Attributes = MemberAttributes.Family;
m.AddParameter(Easy.TypeRef("INode"), "node");
m = td.AddMethod("EndVisit");
m.Attributes = MemberAttributes.Family;
m.AddParameter(Easy.TypeRef("INode"), "node");
foreach (Type type in nodeTypes) {
if (!type.IsAbstract) {
m = td.AddMethod(typeof(object), VisitPrefix + type.Name);
m.Attributes = MemberAttributes.Public | MemberAttributes.Override;
m.AddParameter(ConvertType(type), GetFieldName(type.Name));
m.AddParameter(new CodeTypeReference(typeof(object)), "data");
CodeExpression var = Easy.Var(GetFieldName(type.Name));
// m.Statements.Add(new CodeMethodInvokeExpression(new CodeMethodReferenceExpression(new CodeThisReferenceExpression(), "BeginVisit"), new CodeExpression[] { var }));
// m.Statements.Add(new CodeVariableDeclarationStatement(new CodeTypeReference(typeof(object)), "result", new CodeMethodInvokeExpression(new CodeMethodReferenceExpression(new CodeThisReferenceExpression(), "TrackedVisit"), new CodeExpression[] { var, new CodeVariableReferenceExpression("data") })));
// m.Statements.Add(new CodeMethodInvokeExpression(new CodeMethodReferenceExpression(new CodeThisReferenceExpression(), "EndVisit"), new CodeExpression[] { var }));
// m.Statements.Add(new CodeMethodReturnStatement(new CodeVariableReferenceExpression("result")));
m.Body.InvokeMethod(Easy.This, "BeginVisit", var);
m.Body.DeclareVariable(typeof(object), "result").InitExpression
= Easy.This.InvokeMethod("TrackedVisit" + type.Name, var, Easy.Var("data"));
m.Body.InvokeMethod(Easy.This, "EndVisit", var);
m.Body.Return(Easy.Var("result"));
}
}
foreach (Type type in nodeTypes) {
if (!type.IsAbstract) {
m = td.AddMethod(typeof(object), "TrackedVisit" + type.Name);
m.Attributes = MemberAttributes.Public;
m.AddParameter(ConvertType(type), GetFieldName(type.Name));
m.AddParameter(new CodeTypeReference(typeof(object)), "data");
m.Body.Return(Easy.Base.InvokeMethod(VisitPrefix + type.Name, Easy.Var(GetFieldName(type.Name)), Easy.Var("data")));
}
}
return td;
}
static CodeTypeDeclaration CreateAstVisitorClass(List<Type> nodeTypes, bool transformer)
{
EasyTypeDeclaration td = new EasyTypeDeclaration(transformer ? "AbstractAstTransformer" : "AbstractAstVisitor");
td.TypeAttributes = TypeAttributes.Public | TypeAttributes.Abstract;
td.BaseTypes.Add(new CodeTypeReference("IAstVisitor"));
if (transformer) {
string comment =
"The AbstractAstTransformer will iterate through the whole AST,\n " +
"just like the AbstractAstVisitor. However, the AbstractAstTransformer allows\n " +
"you to modify the AST at the same time: It does not use 'foreach' internally,\n " +
"so you can add members to collections of parents of the current node (but\n " +
"you cannot insert or delete items as that will make the index used invalid).\n " +
"You can use the methods ReplaceCurrentNode and RemoveCurrentNode to replace\n " +
"or remove the current node, totally independent from the type of the parent node.";
Easy.AddSummary(td, comment);
EasyField field = td.AddField(Easy.TypeRef("Stack", "INode"), "nodeStack");
field.InitExpression = Easy.New(field.Type);
/*
CodeExpression nodeStack = Easy.Var("nodeStack");
CodeMemberProperty p = new CodeMemberProperty();
p.Name = "CurrentNode";
p.Type = new CodeTypeReference("INode");
p.Attributes = MemberAttributes.Public | MemberAttributes.Final;
p.GetStatements.Add(new CodeMethodReturnStatement(new CodeVariableReferenceExpression("currentNode")));
p.SetStatements.Add(new CodeAssignStatement(new CodeVariableReferenceExpression("currentNode"),
new CodePropertySetValueReferenceExpression()));
td.Members.Add(p);
*/
EasyMethod m = td.AddMethod("ReplaceCurrentNode");
m.AddParameter(Easy.TypeRef("INode"), "newNode");
m.Statements.Add(Easy.Var("nodeStack").InvokeMethod("Pop"));
m.Statements.Add(Easy.Var("nodeStack").InvokeMethod("Push", Easy.Var("newNode")));
m = td.AddMethod("RemoveCurrentNode");
m.Statements.Add(Easy.Var("nodeStack").InvokeMethod("Pop"));
m.Statements.Add(Easy.Var("nodeStack").InvokeMethod("Push", Easy.Null));
}
foreach (Type type in nodeTypes) {
if (!type.IsAbstract) {
EasyMethod m = td.AddMethod(typeof(object), VisitPrefix + type.Name);
m.Attributes = MemberAttributes.Public;
m.AddParameter(ConvertType(type), GetFieldName(type.Name));
m.AddParameter(typeof(object), "data");
List<CodeStatement> assertions = new List<CodeStatement>();
string varVariableName = GetFieldName(type.Name);
EasyExpression var = Easy.Var(varVariableName);
assertions.Add(AssertIsNotNull(var));
AddFieldVisitCode(m, type, var, assertions, transformer);
if (type.GetCustomAttributes(typeof(HasChildrenAttribute), true).Length > 0) {
if (transformer) {
m.Statements.Add(new CodeSnippetStatement(CreateTransformerLoop(varVariableName + ".Children", "INode")));
m.Body.Return(Easy.Null);
} else {
m.Body.Return(var.InvokeMethod("AcceptChildren", Easy.This, Easy.Var("data")));
}
} else {
CodeExpressionStatement lastStatement = null;
if (m.Statements.Count > 0) {
lastStatement = m.Statements[m.Statements.Count - 1] as CodeExpressionStatement;
}
if (lastStatement != null) {
m.Statements.RemoveAt(m.Statements.Count - 1);
m.Body.Return(lastStatement.Expression);
} else {
m.Body.Return(Easy.Null);
}
}
for (int i = 0; i < assertions.Count; i++) {
m.Statements.Insert(i, assertions[i]);
}
}
}
return td;
}
