Re: [xsl] Re: Keeping a running total?

[Steve <subsume@xxxxxxxxx>]

Thank you for your comments.

I suspect I am simply not a high-enough level user to exploit these
benefits to any degree, but I can understand their benefit. However, I
suspect that an option to make variables modifiable--at the expense of
the points mentioned--would come under wide use, quickly. =)

*Goes away for 3 days to understand how Dimitre's solution actually works*

-S

On 7/12/06, Colin Adams <colinpauladams@xxxxxxxxxxx> wrote:
> This is the normal situation for functional (as opposed to imperative)
> languages.
>
> Benefits:
>
> 1) Transparency - it is far easier to reason about a program that is free
> from side effects. So
>     you can prove your program is correct with less effort.
> 2) Scalability - pure (side-effect free) programs are much easier to
> parallelize
> 3) Learning - variables in functional programs are the same as variables in
> mathematics - you don't
>                    have to learn a new concept (assingment)
> 4) Debugging - no need to monitor when a variable changes value.
> 5) Power - you can bind a variable to a function definition, then it can be
> passed as the argument
>                 of a function (see FXSL)
>
> Downsides:
>
> 1) Performance - functional languages are stil slower than imperative
> languages, although the gap is closing.
> 2) Large scale program structure - OO programming seems to have the
> advantage here.
>
> >From: Steve <subsume@xxxxxxxxx>
> >Reply-To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> >To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> >Subject: Re: [xsl] Re: Keeping a running total?
> >Date: Wed, 12 Jul 2006 12:52:59 -0400
> >
> >Forgive me for the tangent, especially if it sounds ignorant, but as a
> >newbie to XSL I have a hard time understanding the benefit in not
> >being able to redefine a variable.  While I do not doubt the talent
> >and genius that went into the above examples and speculations, I can't
> >imagine a benefit that outweighs the time economics involved in coming
> >up with the above solutions, versus simply doing a $variable =
> >$variable - $x and being done with it in 10ish lines.
> >
> >Comments welcome.
> >
> >-Steve
> >
>
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