INSTANTANEOUS SYMBOL LOOKUP

A computer program assists in the completion of text input provided by a user. For example, the computer program may maintain a list of n-tuples (where n>1), each of which includes n text strings. For example, each n-tuple may include a stock ticker symbol and the name of a company having that stock ticker symbol. As the user types each character, the program determines whether the text typed by the user so far matches any of the text strings in the n-tuples. The program provides the user with an indication of whether any matches have been found, such as by displaying a list of the n-tuples having text matching the text typed by the user so far. The program then allows the user to select one of the matching n-tuples. The program uses text (such as a stock ticker symbol) from the user's selection to complete the text input.