parse-number

[Bernard S. Greenberg <BSG at SCRC-TENEX at mit-mc>]

    Date: Thursday, 23 December 1982, 13:40-EST
    From: Daniel L. Weinreb <dlw at SCRC-TENEX>
    Ah.  That reminds me why parse-number works the way it does.
    parse-number is intended to be a tool to help you parse your way through
    a string.  If you encounter a digit on your way from the left end of the
    string to the right end, you call parse-number, and it reads in as much
    of the string as is a number and tells you where it stopped so that you
    can continue to parse the string.  Whether you expected the entire
    string to be a number or not is up to you, and parse-number can be
    useful in both cases so the "best" default value for the
    fail-if-not-whole-string argument is not obvious.  I don't think it's
    too important as long as the documentation makes it clear.
Now I see.  So parse-number is designed to help you implement user interfaces
where fields are delimited from each other by what kind of characters they
contain, not spaces, commas, or other such.  I have used parse-number countless
times since I came here, and not once wanted its current behavior.  Does anyone
acknowledge this point about the current behavior implying peculiar user interfaces?