Is faster using abbreviated parameter names?


#1

Hi, a simple question:

a)
def hello(string)
# stuff with ‘string’
end

b)
def hello(s)
# stuff with ‘s’
end

Will be b) faster since the parameter name contains less letters?


#2

On 02.03.2009 21:48, Iñaki Baz C. wrote:

end

Will be b) faster since the parameter name contains less letters?

I have no idea. I guess not. But you can easily verify for yourself.
Just write up a little program using Benchmark and you’ll soon know.

Kind regards

robert


#3

El Lunes, 2 de Marzo de 2009, Robert K.
escribió:> > # stuff with ‘s’

end

Will be b) faster since the parameter name contains less letters?

I have no idea. I guess not. But you can easily verify for yourself.
Just write up a little program using Benchmark and you’ll soon know.

Yes, doing a benchmark the result is more or less the same (any other
factor
seems to be more important), but what I want to know is what should be
the
response based on how Ruby works. Under my understanding Ruby needs to
parse
during runtime the variable name so a longer variable name would require
more
time, am I wrong?

Thanks a lot.


#4

Iñaki Baz C. wrote:

Yes, doing a benchmark the result is more or less the same (any other
factor
seems to be more important), but what I want to know is what should be
the
response based on how Ruby works. Under my understanding Ruby needs to
parse
during runtime the variable name so a longer variable name would require
more
time, am I wrong?

I believe you’re wrong.

Symbols are resolved into references to the symbol table at parse time,
so when running, :s and :ssssssssssssssss are just two different
pointers into the same symbol table. As for local variables, they are
just offsets into the stack frame.

So it might take a microscopically small amount of extra time for your
program to start up, reading a few extra bytes of source code, but once
it’s running, each iteration should take the same time.


#5

And how much faster would it have to be to make it worth it to use a
meaningless name versus a meaningful one?

Smells like premature optimization to me…

Cheers,

dwh


#6

El Lunes, 2 de Marzo de 2009, Brian C. escribió:

I believe you’re wrong.

Symbols are resolved into references to the symbol table at parse time,
so when running, :s and :ssssssssssssssss are just two different
pointers into the same symbol table. As for local variables, they are
just offsets into the stack frame.

So it might take a microscopically small amount of extra time for your
program to start up, reading a few extra bytes of source code, but once
it’s running, each iteration should take the same time.

Thanks, that makes sense :slight_smile:


#7

Good to hear.

It’s just remarkable how lots of people start at the end and work their
way backwards… :wink:

dwh


#8

El Lunes, 2 de Marzo de 2009, Denis H. escribió:

And how much faster would it have to be to make it worth it to use a
meaningless name versus a meaningful one?

Smells like premature optimization to me…

Sure, it was just curiosity :slight_smile:
I will not code in Ruby to get a unreadable code like in other languages
:slight_smile: