Re: Initial Draft Finding on Principle of Least Power

Graham Klyne wrote:
> Harry Halpin wrote:
>> I might add that the characterization of functional programming
>>languages as somehow  "less powerful" than procedural languages might
>>want to be - i.e. "through those that are functional and Turing complete
>>(Haskell), to those which are unashamedly procedural (Java, Javascript,
>>C)" - should be rephrased, since this will offend functional programmers
>>who would argue the *exact* opposite :)
> I'm biased in this respect, but I rather liked the reference to Haskell.  In
> particular, I thought the text was clear enough (to me) that Haskell was no less
> powerful, but also carried the suggestion that somehow pure functional
> expressions are more amenable to the proffered advantages of less power.

I've been following this thread, and believing myself to be in target
audience for such principles. I guess my question is this: why would I
follow this principle?

This strikes me as the key statement to chew on from the original:

"Nowadays we have to appreciate the reasons for picking not the most
powerful solution but the least powerful. The reason for this is that
the less powerful the language, the more you can do with the data stored
in that language."

The spectacle of initially and deliberately weak languages that have had
to have extra expressive power bolted on is so very common, and flies in
the face of this advice, that I wonder if this principle is applicable.

Web templating languages are something much more relevant to this
principle that SQL revisions.  Rather than talking about Haskell, it
would better to see how following this advice could have provided
guidance to say, someone designing a templating language like JSP/ZPT,
or a serialization/wire format like JSON- which begs the question of
remote evaluation or code sharing (ie should this be a security principle?).

I saw this from the new one:

"Good Practice: Use the least powerful language suitable for expressing
information, constraints or programs on the World Wide Web."

My main concern is that there is no overriding, non-local principle that
can be applied to language selection on the Web, which seems to be the
context for this principle. In other words there could be an equally
valid Principle of Most Power. Outside the web, this an ongoing
discussion in terms of Domain Specific Languages (DSLs) - one school of
though says to use what we might call full-blown language and hope the
lanaguges don't overwhelm the users; another says write something less
expressive and hope the users don't overwhelm the languages.


Received on Thursday, 22 December 2005 11:35:49 UTC