I would disagree, since hash lookups aren't exactly slow. And, sometimes speed isn't always what you want in a script. If I always wanted the fastest way, I would likely use C much of the time instead of Perl. Sometimes, you want what makes most sense to "you", and what "you" find intuitive. Here is an example, sort of the same concept, but a little different...

I had to work on a project that someone else worked on. All his DBI fetchs would be returned into arrays, maybe for the same reasons you are talking about. So, much of the code looked like: 

do something with $array[8]
Now, do something with $array[9]

[download]

Well, that means nothing to me. How do I know that the 8th element is the 'FNAME' field and the 9th is the 'LNAME' field? I don't! Also, what happens when you change the table? BAM! Things can get seriously out of whack if I make a 'MNAME' field after the 'FNAME' field.

So, I started off by changing all his fetchrow_array's to fetchrow_hashref's. Now, I had a more intuitive (and scalable) way to do things like: 

do something with $hashref->{FNAME}
do something else with $hashref->{LNAME}
Don't forget $hashref->{MNAME}

[download]

Did I sacrifice some speed by using a hash(ref)? Maybe. Is the script now easier to read and maintain? Definitely! So, which is more efficient? I say it is more efficient to have readable and maintainable code. This saves work-time, which is much more measurable than fractions of a second differences that may be gained/lost with using one data structure vs. another.

So, I disagree that it is more efficient to use an array, based on my experiences. But, regardless, this was an exercise to find AWTDI ;-)

Cheers,
KM

In reply to Re: Re: Re: Re: Reading file into a numbered hash by KM
in thread Reading file into a numbered hash by KM

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