Re: Reading the while standard input into a String

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

"J-P. Rosen" <rosen@adalog.fr> wrote in message 
news:isj8f2$485$1@dont-email.me...
...
> I once doubled the speed of a compiler by rewriting the main character
> reading procedure in assembly. A compiler spends more time than you
> would think simply skipping spaces...
> (Yes, I did measure that - TBH, it was quite a long time ago, on a
> computer that was very different from what we have today).

System calls are expensive on every machine I've ever seen. I've yet to see 
a case where it is better to let the system buffer the input rather than do 
it yourself. I ended up moving that into Ada.Text_IO after dealing with 
customers that were not willing to believe that fact.

As far as compilers go, I recall that most of the syntax pass was coded in 
assembler in the early days of Janus/Ada; and it far more than doubled the 
speed over the Ada version (it was closer to a factor of 10). We maintained 
both versions for many years. On more modern machines, with compilers that 
have much better optimization, I've been able to get rid of that assembler 
code.

                                               Randy.