From: Chris Thomas <cjack@...>
Date: 2002-04-04T01:04:53+09:00
Subject: Re: About efficiency


On Tuesday, April 2, 2002, at 05:46 PM, Sean Middleditch wrote:

>>> I have been enjoying Ruby for 2 weeks now. I am very impressed. It is
>>> my understanding that currently the interpreter directly executes the
>>> parse tree versus going thru some bytecode generation phase (the later
>>> is what I did for some interpreter I wrote years ago, while at the
>>> same time a friend of mine was going the ruby way, hence we had
>>> opportunities to compare).
>>
>> Ruby VM is planned.
>
> VM's make things a *lot* faster.  I'm experimenting with Scriptix, and
> taking it from the Ruby-ish nodes to a byte-code language improved the
> speed by 1.5-3 times, depending on the test (I'm no profressional
> benchmark writer, mind you).

I'm curious, do you know exactly where the speed gains come from in your 
implementation? Is it from the elimination of the need to parse the code 
every time it's run, or from something else?

If the gain is made by eliminating the need to parse the source, 
presumably one could make similar gains simply by flattening the tree 
representation.

(I ask because it doesn't seem logical to me that interpreting bytecode 
should be inherently faster than interpreting tree nodes.)

Chris