public virtual object Walk(SelfExpression node)
{
if (Enter(node))
{
// Insert code here
}
Exit(node);
return(null);
}
private SelfExpression ParseSelfExpression()
{
var exp = new SelfExpression {
Token = Next()
};
Match(TokenType.This);
return(exp);
}
private IExpression ParseCallExpression(IExpression receiver)
{
CallExpression exp;
if (CurTokenIs(TokenType.LParen))
{
var m = ((Identifier)receiver).Value;
var selftok = new Token {
Type = TokenType.Self, Literal = "self", Line = CurToken.Line
};
var self = new SelfExpression {
Token = selftok
};
receiver = self;
exp = new CallExpression {
Token = CurToken, Receiver = receiver, Method = m
};
exp.Arguments = ParseCallArguments();
}
else
{
exp = new CallExpression {
Token = CurToken, Receiver = receiver
};
if (!ExpectPeek(TokenType.Ident))
{
return(null);
}
exp.Method = CurToken.Literal;
if (PeekTokenIs(TokenType.LParen))
{
NextToken();
exp.Arguments = ParseCallArguments();
}
else
{
exp.Arguments = new List <IExpression>();
}
}
if (PeekTokenIs(TokenType.Assign))
{
exp.Method = exp.Method + "=";
NextToken();
NextToken();
exp.Arguments.Add(ParseExpression(LOWEST));
}
if (PeekTokenIs(TokenType.Do))
{
ParseBlockParameters(exp);
}
return(exp);
}
public void Evaluate()
{
Machine machine = new Machine();
SelfExpression expr = new SelfExpression();
var result = expr.Evaluate(machine.RootContext);
Assert.IsNotNull(result);
Assert.AreSame(machine.RootContext.Self, result);
}
public void ParseSelfExpression()
{
Parser parser = new Parser("self");
var expected = new SelfExpression();
var result = parser.ParseExpression();
Assert.IsNotNull(result);
Assert.AreEqual(expected, result);
Assert.IsNull(parser.ParseCommand());
}
public void Equals()
{
SelfExpression expr1 = new SelfExpression();
SelfExpression expr2 = new SelfExpression();
Assert.IsFalse(expr1.Equals(null));
Assert.IsFalse(expr1.Equals(123));
Assert.IsFalse(expr1.Equals("foo"));
Assert.IsTrue(expr1.Equals(expr2));
Assert.IsTrue(expr2.Equals(expr1));
Assert.AreEqual(expr1.GetHashCode(), expr2.GetHashCode());
}
private IExpression ParseDefExpression()
{
string name = this.ParseName();
INamedExpression named = null;
if (name == "self")
{
named = new SelfExpression();
}
else
{
named = new NameExpression(name);
}
while (true)
{
if (this.TryParseToken(TokenType.Separator, "."))
{
string newname = this.ParseName();
named = new DotExpression(named, newname, new IExpression[0]);
continue;
}
if (this.TryParseToken(TokenType.Separator, "::"))
{
string newname = this.ParseName();
named = new DoubleColonExpression(named, newname);
continue;
}
break;
}
IList <string> parameters = this.ParseParameterList();
IExpression body = this.ParseCommandList();
return(new DefExpression(named, parameters, body));
}
private ClassExpression ParseClassExpression()
{
string name = this.ParseName();
INamedExpression named = null;
if (name == "self")
{
named = new SelfExpression();
}
else
{
named = new NameExpression(name);
}
while (true)
{
if (this.TryParseToken(TokenType.Separator, "::"))
{
string newname = this.ParseName();
named = new DoubleColonExpression(named, newname);
continue;
}
break;
}
this.ParseEndOfCommand();
IExpression body = this.ParseCommandList();
if (!Predicates.IsConstantName(named.Name))
{
throw new SyntaxError("class/module name must be a CONSTANT");
}
return(new ClassExpression(named, body));
}
private SelfExpression ParseSelfExpression()
{
var exp = new SelfExpression {Token = Next()};
Match(TokenType.This);
return exp;
}
public virtual object Walk(SelfExpression node)
{
if (Enter(node))
{
// Insert code here
}
Exit(node);
return null;
}
public override bool Enter(SelfExpression node)
{
Print("SelfExpression");
level++;
return true;
}
public override void Exit(SelfExpression node)
{
level--;
}
public virtual bool Enter(SelfExpression node)
{
return true;
}
public virtual void Exit(SelfExpression node)
{
}
public virtual bool Enter(SelfExpression node)
{
return(true);
}
public virtual void Exit(SelfExpression node)
{
}
public virtual void Accept(SelfExpression self)
{
}
public override object Walk(SelfExpression node)
{
return Context.CurrentFrame.Resolve("this");
}
public override bool Enter(SelfExpression node)
{
Print("SelfExpression");
level++;
return(true);
}
public override object Walk(SelfExpression node)
{
return(Context.CurrentFrame.Resolve("this"));
}
public override void Exit(SelfExpression node)
{
level--;
}
