DCT: D compiler as a collection of libraries

[Roman D. Boiko]

On Friday, 11 May 2012 at 15:05:19 UTC, deadalnix wrote:
> Le 11/05/2012 16:02, Roman D. Boiko a écrit :
>> Technically, I'm trading N*0(1) operations needed to track 
>> line and
>> column while consuming each character to M*0(log(n)) 
>> operations when
>> calculating them on demand. N = number of characters, n is 
>> number of
>> lines and M is number of actual usages of Location. My 
>> assumption is
>> that M << N (M is much smaller than N).
>
> N can easily be number of tokens.
Yes, if you are looking for the token by its index, not for 
location. E.g., for autocompletion it is needed to find the last 
token before cursor location. But that is not related to location 
search.

Also please note that I oversimplified formula for complexity. It 
also has other components. My reply was just an additional minor 
comment. Motivation is design, not performance.

One additional reason for such separation: with my approach it is 
possible to calculate Location both taking into account 
infromation from special token sequences, or ignoring it. How 
would you do that for eager calculation? Calculate only one 
category? Or track and store both?

Unnecessary complexity will eventually find a way to shoot your 
leg :) Real-world usage (at least, anticipated scenarios) should 
be the basis for designing. Sometimes this contradicts intuition 
and requires you to look at the problem from a different side.