Re: basic char and int array loading

From: zentara (zentara_at_highstream.net)
Date: 12/13/04 

Date: Mon, 13 Dec 2004 07:21:16 -0500

On Sun, 12 Dec 2004 01:21:03 +0100, Ulrich Eckhardt <doomster@knuut.de>
wrote:

>
>This calls operator>>( istream&, int&). If you enter e.g. 'e', the operator
>will try to convert that input to a number and fail. The input remains in
>the stream's buffer and all subsequent input operations will fail, until
>you clear() the stream.
>
>If you want the byte-value of an entered char, you need to read it as such:
> char tmp;
> cin>>tmp;
> // convert to unsigned char first to suppress sign promotion
> unsigned value = static_cast<unsigned char>(tmp);
>
>BTW:
>- you can do more than 'i++' in the for statement, e.g. 'i++, j++'
>- in that loop, i always has the same value as j
>- you can declare and initialise vars in a for statement:
> for(int i(0); i!=5; ++i) { ... }
>- a char has always size 1, not only on your system. An int doesn't always
>have size 4 though, that's just your system.

Thanks for the insights. The explanation of the failed data remaining
in the stream's buffer now makes things understandable.

Comparing this to Perl, I don't worry about whether a piece of data
is string or numeric. So I was wondering, is there a generally used
way in C++, to load an array with a combination of strings and numerics,
so that it is all handled gracefully, or do I need to do all the testing
and clearing myself?

Do you just pull everything in as strings, and worry about converting
string to int or double later? 

-- 
I'm not really a human, but I play one on earth.
http://zentara.net/japh.html

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