stdio performance in tango, stdlib, and perl

[Daniel Keep]

Vladimir Panteleev wrote:
> On Thu, 22 Mar 2007 11:03:12 +0200, Daniel Keep <daniel.keep.lists at gmail.com> wrote:
> 
>>> 4) it's much easier to add a line ending than to remove it.
>> Actually, it's not.  Removing a line ending is as simple as slicing the
>> string.  *Adding* a line ending could involve a heap allocation, at
>> least a full copy.
> 
> I was actually talking about the complexity of the source, not the efficiency of the generated code.
> When readln gives you the line with a line ending, you have three cases:
> 1) a CR/LF line ending (Windows)
> 2) LF line ending (Unix)
> 3) no line ending at all (EOF)
> 
> You'd need to account for every of these when removing the line endings - and write this code every time you're writing an app which just needs the contents of lines from standard input - which, as you have agreed, is quite common.

import std.string;

auto line = readln().chomp();

:)

>> What's more, how can you be sure there was a line-ending there at all?
>> What if it's the last line and it didn't have a line ending before EOF?
> 
> IMHO, most tools which work with standard input don't really need to know if the last line has a line break at the end :)
>

-- 
int getRandomNumber()
{
    return 4; // chosen by fair dice roll.
              // guaranteed to be random.
}

http://xkcd.com/

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