public ListAccess ParseListAccess(Token token)
{
Token identifier = token;
this.Consume(TokenType.LEFT_SQUARE_BRACKET);
Token indexer = lexer.Next();
AST index = null;
if (indexer.Is(TokenType.IDENTIFIER))
{
index = new Tree.Variable(indexer.Value);
}
else if (indexer.Is(TokenType.NUMBER))
{
index = new Tree.Number(indexer.Value);
}
else if (lexer.Peek().isOperator())
{
index = this.Expression(indexer);
}
else
{
this.Error("List accesser not allowed. ", indexer);
}
this.Consume(TokenType.RIGHT_SQUARE_BRACKET);
return(new ListAccess(identifier.Value, index));
}
public AST ParseListReAssignment(Token token)
{
this.Consume(TokenType.LEFT_SQUARE_BRACKET);
Token index = lexer.Next();
this.Consume(TokenType.RIGHT_SQUARE_BRACKET);
AST indexer = null;
if (index.Is(TokenType.IDENTIFIER))
{
indexer = new Tree.Variable(index.Value);
}
else if (index.Is(TokenType.NUMBER))
{
indexer = new Tree.Number(index.Value);
}
else
{
this.Error("Only variables or numbers can be used to access list items", index);
}
AST right = null;
if (lexer.Peek().Is(TokenType.IS))
{
//there is the right part;
this.Consume(TokenType.IS);
right = this.Assignee();
}
else if (lexer.Peek().Is(TokenType.SEMI_COLON))
{
right = new Tree.Null();
}
ListModify modifier = new ListModify(token.Value, indexer, right);
return(new ReAssignment(token.Value, modifier));
}