Re: Postel's law

On May 24, 1:18 am, Marshall <marshall.spi..._at_gmail.com> wrote:
> On May 22, 10:28 pm, David BL <davi..._at_iinet.net.au> wrote:
>
> > Have you heard of Postel's Law?
>
> > "Be liberal in what you accept, and conservative in what you send."
>
> > I can imagine it being applied to many things. Eg file formats, APIs,
> > compilers, databases ...
>
> > I think it generally leads to unnecessary complexity and sweep errors
> > under the carpet.
>
> Postel's law makes enormous intuitive sense. Its benefits are
> immediately obvious. There's just the one teeny problem that it
> leads to widespread ruination.
>
> Many related arguments, and in some cases Postel's Law in
> particular, have been used to justify various wonky behaviors
> in Haphazard Text Markup Language parsers. The argument
> goes something along the line of, any file you can get anything
> out of, you ought to. And also that this enables shitty amateurs
> to write code that writes files.

Developers that assume their end users are shitty amateurs get what they ask for.

> This defeats the purpose of having a standard in the first place.

This is my biggest problem with Postel's law.

> The counter argument for me has always been JPEG. JPEG
> may actually be such a success *because* it's so technically
> difficult. You don't get shitty amateurs writing JPEG writers.
> They just use a library that already works, which was written
> by an actual expert. (Which is what the "E" in "JPEG" stands
> for anyway.) And JPEG is an enormously successful file
> format; there are probably more JPEG files on the web than
> HTML files.

It's amazing how XML on the one hand is promoted as a text format that can be freely edited in your favourite text editor, and on the other hand its verboseness is a godsend because it puts people off actually doing so. Received on Sat May 24 2008 - 03:14:57 CEST