I'm trying my hand at reading from standard input and having little luck. In particular, I would like to be able to do the rough equivalent of C++'s:

cin >> myString;

As opposed to reading the whole line.

I attempted to do this with readf:

string result;
readf(" %s ", &result);

However this does not seem to do the trick. If I enter "Hello\n" on the terminal, it keeps waiting for input. By contrast, if I enter "Hello program", it correctly identifies "Hello" as the 'result'.

Thus, contrary to what I've been reading, the trailing space seems to only account for space characters, not general whitespace.

I presume that I'm missing something obvious, any ideas?


Thanks in advance!

Mark Isaacson:

> I'm trying my hand at reading from standard input and having little luck. In particular, I would like to be able to do the rough equivalent of C++'s:
>
> cin >> myString;

There isn't always a 1:1 mapping between C++ and D. In D if you want a single word you usually read the whole line (with a byLine) and then you use split or splitter to take the single words.

Something like this (untested):

foreach (line; stdin.byLine) {
    immutable words = line.chomp.idup.split;
}

Bye,
bearophile

Fair enough. I've done stuff like that in the past. I'm trying to implement a university project that was originally designed for C++ style I/O... and so where I'd have otherwise jumped at something like that from the beginning, my hands are slightly tied.

Suppose I'll make due/not fully comply with the spec.

Mark Isaacson:

> Fair enough. I've done stuff like that in the past. I'm trying to implement a university project that was originally designed for C++ style I/O... and so where I'd have otherwise jumped at something like that from the beginning, my hands are slightly tied.

If you need/want to use the C++ style, even if it's not fully Phobos-idiomatic, probably you can invent some way to simulate it.

Bye,
bearophile

Indeed. However, doing so looks more painful than redefining my goals. Upon further examination it seems that I had more flexibility than I originally estimated. Besides, the real reason I'm implementing this project is just to practice for when I get to write production D code in a week anyway; I'd rather learn the idioms.

Mark Isaacson:

> Indeed. However, doing so looks more painful than redefining my goals. Upon further examination it seems that I had more flexibility than I originally estimated. Besides, the real reason I'm implementing this project is just to practice for when I get to write production D code in a week anyway; I'd rather learn the idioms.

OK. Once you are done with this little project you can post a link here, I can review the code a little if you want.

Bye,
bearophile

An exceptionally generous offer! May take you up on that. Thank you :).