public static FunctionHeader Header(MatchIterator iterator)
{
iterator.AssertTokenType(TokenType.Type, out Token typeToken);
iterator.AssertTokenType(TokenType.Name, out Token nameToken);
iterator.AssertKeySymbol(Symbols.OpenBracket, out _);
Token open = (Token)iterator.Current;
CollectedParameters parameters;
if (iterator.Next(out parameters))
{
iterator.MoveNext();
}
else
{
parameters = new CollectedParameters();
}
iterator.AssertKeySymbol(Symbols.CloseBracket, out _);
Token end = (Token)iterator.Current;
iterator.AssertEnd();
FunctionTypeSignature typeSignature = new FunctionTypeSignature(parameters.Types);
FunctionSignature signature = new FunctionSignature(
FunctionSignature.Local, nameToken.Content, typeSignature);
FunctionHeader result = new FunctionHeader(
typeToken, nameToken, open, end, signature, parameters.Names);
return(result);
}
public static FunctionCall Call(MatchIterator iterator)
{
// It would be cool in patterner v2 if the pattern was constructed in the same method as the finalizer.
// For example, a "dummy" matchIterator could be passed through here and pick up the requirements, perhaps?
// This would, of course, require the big feature of pattern simplification
// It would also require defining a special "Expression" subpattern? At this point it would be better if everything were an expression, I guess
iterator.AssertTokenType(TokenType.Name, out Token name);
iterator.AssertKeySymbol(Symbols.OpenBracket, out _);
Token open = (Token)iterator.Current;
if (iterator.Next(out List <Expression> arguments))
{
iterator.MoveNext();
}
else
{
arguments = new List <Expression>();
}
iterator.AssertKeySymbol(Symbols.CloseBracket, out _);
Token end = (Token)iterator.Current;
iterator.AssertEnd();
FunctionCall result = new FunctionCall(name, open, end, arguments);
return(result);
}
public static VariableAssignment Assignment(MatchIterator iterator)
{
if (!iterator.NextIsToken(TokenType.Type, out Token type))
{
type = null;
}
iterator.AssertTokenType(TokenType.Name, out Token name);
if (iterator.Next(out List <CollectedIndex> indices))
{
iterator.MoveNext();
}
else
{
indices = new List <CollectedIndex>(0);
}
iterator.AssertTokenType(TokenType.Operator, out Token op);
if (!iterator.NextIsExpression(out Expression value))
{
value = null;
}
iterator.AssertEnd();
return(new VariableAssignment(type, name, indices, op, value));
}
public static Expression CreateOld(MatchIterator iterator)
{
Token opToken;
if (iterator.NextIsToken(TokenType.Operator, out opToken))
{
// assume a left operator for now
Expression righExpr = Create(iterator);
return(new OperatorCall(opToken, null, righExpr));
}
Expression nextExpr;
if (iterator.NextIsKeySymbol(Symbols.OpenBracket))
{
iterator.AssertExpression(out nextExpr);
iterator.AssertKeySymbol(Symbols.CloseBracket, out _);
}
else
{
iterator.AssertExpression(out nextExpr);
}
if (iterator.AtEnd())
{
return(nextExpr);
}
if (iterator.Next(out List <CollectedIndex> indices))
{
foreach (CollectedIndex index in indices)
{
nextExpr = new Indexer(nextExpr, index.Open, index.Index, index.Close);
}
iterator.MoveNext();
}
if (iterator.AtEnd())
{
return(nextExpr);
}
iterator.AssertTokenType(TokenType.Operator, out opToken);
if (iterator.AtEnd())
{
// Assume a right operator for now
return(new OperatorCall(opToken, nextExpr, null));
}
// Assume a binary operator for now
Expression remainder = Create(iterator);
return(new OperatorCall(opToken, nextExpr, remainder));
}
private static Expression GetValue(MatchIterator iterator)
{
if (iterator.NextIsToken(TokenType.Operator, out Token opToken))
{
// Early out: if we are starting with an operator, than it is
// a right unary operator, and unary ops have the highest
// precedence at the moment.
return(new OperatorCall(opToken, null, GetValue(iterator)));
}
Expression expression;
// We don't have to recursively descend through the brackets -
// that is handled at the pattern matching level. As far as we are
// concerned, there are either expressions or expressions wrapped
// in brackets.
if (iterator.NextIsKeySymbol(Symbols.OpenBracket, out Token open))
{
iterator.AssertExpression(out Expression value);
iterator.AssertKeySymbol(Symbols.CloseBracket, out Token close);
expression = new Group(open, value, close);
}
else
{
iterator.AssertExpression(out expression);
}
// Finally, consider any indexing that follow the expression.
// Sprak only allows one level of this, but that will be enforced
// later where a more friendly error can be displayed.
if (iterator.Next(out List <CollectedIndex> indices))
{
foreach (CollectedIndex index in indices)
{
expression = new Indexer(expression, index.Open, index.Index, index.Close);
}
iterator.MoveNext();
}
return(expression);
}
public static LiteralArrayGet CreateArray(MatchIterator iterator)
{
Token start, end;
iterator.AssertKeySymbol(Symbols.OpenSquareBracket, out _);
start = (Token)iterator.Current;
if (iterator.Next(out List <Expression> elements))
{
iterator.MoveNext();
}
else
{
elements = new List <Expression>();
}
iterator.AssertKeySymbol(Symbols.CloseSquareBracket, out _);
end = (Token)iterator.Current;
return(new LiteralArrayGet(start, end, elements));
}