[boost] Re: Re: IOStreams formal review start

From: Jonathan Turkanis (technews_at_[hidden])
Date: 2004-08-31 10:55:19

"Reece Dunn" <msclrhd_at_[hidden]> wrote in message
news:BAY24-F33zTGBGrhUaC00059ac2_at_hotmail.com...

> If you want to read a bzip2 file (for example), the bzip2 file will be a
> binary stream and the resulting stream will be either binary or text
> depending on what the compressed file stores. You can tell std::ifstream to
> read the stream as binary, so what is the problem? Also, you might want to
> convert between text and binary modes:
>
>    file > bzip2 (binary) > text > (process) > bzip2 (binary) > file

Line-ending conversions can be done by sticking a newline filter in between the
binary and text filters. When converting_stream is up and running, code
conversion will be inserted at the appropriate place in a filter chain
consisting of mixed narrow- and wide-character components.

> > > 1.  Actual code using this library is very slick and easy to set up.
> >This
> > > ease of use/set-up also applies to the plug-in filters and/or resources.
>
> I also like the ability to chain filters. I have a program that uses a
> similar mechanism on a character tape stream that allows text to be split to
> a certain character length and/or merged back into one block. It would be
> interesting to compare the performance of using my program verses an
> implementation using this library.

I'd be interested too. There are a number of optimization I've held in reserve
because I'm not sure ther'ye necessary. The big question is: what should I
compare my library to?

> >There are two main resons to write Sources and Sinks instead of stream
> >buffers:
> >
> >1. Sources and Sinks and sinks express just the core functionality of a
> >component. Usually you have to implement just one or two functions with

> This is similar to what iterator adaptors and flex_string do for iterators
> and std::strings respectively. This makes it easy to write standard
> conforming components.

Exactly.

> For example, if you wanted to add support for a
> COM-based IStream, it would be easy to implement a source and/or sink.

This was one of the original applications, actually :-)

> I will post a more detailed review once I have had a better look through the
> documentation and library, but at the moment it looks good.

Thanks, I'll look forward to it.

Jonathan