public static Subroutine Parse(Tokenizer tokenizer)
{
tokenizer.CurrentIs(t =>
t is Keyword k && (
k == Keyword.Constructor ||
k == Keyword.Function ||
k == Keyword.Method));
var type = tokenizer.GetCurrentThenMove() as Keyword;
tokenizer.CurrentIs(VaribleType.IsValid);
var returnType = new VaribleType(tokenizer.GetCurrentThenMove());
tokenizer.CurrentIsIdentifier();
var name = tokenizer.GetCurrentThenMove() as Identifier;
var parameters = ParseParameters(tokenizer);
tokenizer.CurrentIs(Symbol.OpenCurly).Move();
var localVaribles = ParseLocalVaribles(tokenizer);
var statements = Statement.ParseStatements(tokenizer);
tokenizer.CurrentIs(Symbol.CloseCurly).Move();
if (type == Keyword.Constructor)
{
return(new Constructor(name, returnType, parameters, localVaribles, statements));
}
if (type == Keyword.Method)
{
return(new Method(name, returnType, parameters, localVaribles, statements));
}
return(new Function(name, returnType, parameters, localVaribles, statements));
}
private void AddClassLevelVaribles(Tokenizer tokenizer)
{
while (tokenizer.Current is Keyword keyword && (
keyword == Keyword.Static || keyword == Keyword.Field))
{
tokenizer.Move().CurrentIs(VaribleType.IsValid);
var type = new VaribleType(tokenizer.GetCurrentThenMove());
tokenizer.CurrentIsIdentifier();
AddVarible(keyword,
new Varible(type, tokenizer.GetCurrentThenMove() as Identifier));
while (tokenizer.Current.Equals(Symbol.Commna))
{
tokenizer.Move().CurrentIsIdentifier();
AddVarible(keyword,
new Varible(type, tokenizer.GetCurrentThenMove() as Identifier));
}
tokenizer.CurrentIs(Symbol.SemiColon).Move();
}
void AddVarible(Keyword keyword, Varible varible)
{
if (keyword == Keyword.Field)
{
Fields.Add(varible);
}
else
{
StaticFields.Add(varible);
}
}
}
protected Subroutine(Identifier name,
VaribleType returnType,
IEnumerable <Varible> arguments,
IEnumerable <Varible> localVaribles,
IEnumerable <Statement> statements)
{
Name = name;
ReturnType = returnType;
Arguments = arguments.ToList();
LocalVaribles = localVaribles.ToList();
Statements = statements;
}
private static IEnumerable <Varible> ParseLocalVaribles(Tokenizer tokenizer)
{
var varibles = new List <Varible>();
while (tokenizer.Current is Keyword keyword && keyword == Keyword.Var)
{
tokenizer.Move().CurrentIs(VaribleType.IsValid);
var type = new VaribleType(tokenizer.GetCurrentThenMove());
tokenizer.CurrentIsIdentifier();
varibles.Add(new Varible(type, tokenizer.GetCurrentThenMove() as Identifier));
while (tokenizer.Current.Equals(Symbol.Commna))
{
tokenizer.Move().CurrentIsIdentifier();
varibles.Add(new Varible(type, tokenizer.GetCurrentThenMove() as Identifier));
}
tokenizer.CurrentIs(Symbol.SemiColon).Move();
}
return(varibles);
}
public Method(Identifier name, VaribleType returnType, IEnumerable <Varible> arguments,
IEnumerable <Varible> localVaribles, IEnumerable <Statement> statements) : base(name, returnType, arguments,
localVaribles, statements)
{
}
public Varible(VaribleType varibleType, Identifier identifier)
{
VaribleType = varibleType;
Identifier = identifier;
}
public override int GetHashCode()
{
unchecked
{
return(((Identifier != null ? Identifier.GetHashCode() : 0) * 397) ^ (VaribleType != null ? VaribleType.GetHashCode() : 0));
}
}