Accessors, byLine, input ranges

[Andrei Alexandrescu]

Michel Fortin wrote:
> On 2010-01-29 12:21:18 -0500, Andrei Alexandrescu 
> <SeeWebsiteForEmail at erdani.org> said:
> 
>> Michel Fortin wrote:
>>> Yeah, it's less likely to be a problem. But "less likely to be a 
>>> problem" does still does not make things reliable. Something reliable 
>>> works all the time, or it just doesn't work and tells you.
>>
>> stream.front after stream.popFront works all the time and fetches a 
>> new line off the stream. Like Steve said, you can't at the same time 
>> fetch a line and leave it back in the stream.
> 
> The problem is that algorithms that depends on this will work with other 
> ranges, but will fail silently when given a stream.

An algorithm can fail in many silent ways if it misuses the range 
interface. None of std.algorithm algorithms uses front naively.

> In all seriousness, even Java streams are better modeled than this 
> (although more limited by not having templates). The basic Java input 
> stream doesn't have a 'front' byte, you can only read the next byte (or 
> the few next bytes). If you need to rewind, there is a standard way, but 
> most streams need to be wrapped in a buffered stream first to provide 
> this capability.

Can you run a basic algorithm on a Java stream and on an array as well?

Andrei