Re: functions, packages & characters

["Randy Brukardt" <randy@rrsoftware.com>]

Hyman Rosen wrote in message <3C753C66.8020509@mail.com>...
>Unversed Angel wrote:
>>  Line_Buffer : String (1 .. 1000);
>
>It's the twenty-first century. Isn't it about time we
>got rid of fixed-size input buffers? Thank goodness
>for the GNU reimplementation of the UNIX utilities,
>which have done away with maximum line sizes, but on
>my Sun, I still can't vi in a 200 column xterm.


Nice try, but he's using Ada.Text_IO.Get_Line, which takes a fixed
length string. So he pretty much has to use a fixed size buffer.

Text_IO doesn't have direct support for unbounded strings (because
having it would drag the unbounded string library into almost every
program, whether you used it or not). Possibly, there ought to be a
Get_Line for Unbounded strings in a child package of Text_IO (but this
does not exist in Ada 95). This would be quite a bit slower than the
regular Get_Line for long lines, but it could be made acceptably fast
for the common case of short lines. It is possible to write such a
Get_Line out of the primitives in Text_IO, but the result would be
unacceptably slow (because you would have to read a character at a
time - you can't use Get_Line because you can't tell between the case of
a line which exactly fills the buffer and a line which is too long and
does not -- but in the former case, the line terminator is skipped).

                      Randy.