Re: List container strawman 1.2

[Florian Weimer <fw@deneb.enyo.de>]

    -- Ideally these routines would verify that Location was issued
    -- for the Subject list and is still valid, but that would be
    -- tough to enforce. Better to call such misuse a "bounded error",
    -- or somesuch.

You should not call it a "bounded error" because that would be
confusing.  Such errors result in erroneous execution with typical
implementations.  For debugging, we might add an additional variable
parameter to the generic, which can be used to enable debugging.  It
should default to "no debugging", and in such cases, at least GNAT
generates no code for "if Debugging then ... end if;" conditional
statements.

Regarding the the name of "Index", I would like to reserve this word
for discrete types.  "Location" or "Position", as proposed by Jeffrey,
is probably better.

What about terminating Iterator prematurely using an exception?  It's
a bit ugly, granted, but with the "out" parameter approach, I've
managed to forget to set the parameter more than once.  If the Quit
parameter is going to stay, we shouldn't use a Boolean type for it,
but a new enumeration type.