From: Robert Klemme <shortcutter@...>
Date: 2009-11-26T01:29:00+09:00
Subject: Re: Ruby internals & other questions

2009/11/25 Ralph Shnelvar <ralphs@dos32.com>:
> Is there a document or website that describes how Ruby works?
>
> For instance ...
>
>
>
> y=0
> 1_000_000.times {|x| y+=x}
>
>
>
> (1) Does the block get compiled a million times?

Of course not.

> (2) What's the best Ruby way to do a sum from 1 to 1_000_000

Same as in other languages: http://en.wikipedia.org/wiki/Arithmetic_series

> (3) Is there a difference in speed between IRB.exe and ruby.exe in
> executing the above code?

Try it out.  Benchmark is your friend.

> (4) In IRB, whats the best way to time the code, above?

irb(main):004:0> require 'benchmark'
=> true
irb(main):005:0> Benchmark.measure { sleep 2 }
=> #<Benchmark::Tms:0x100d2068 @label="", @real=2.0, @cstime=0.0,
@cutime=0.0, @stime=0.0, @utime=0.0, @total=0.0>
irb(main):006:0> Benchmark.measure { sleep 2 }.to_s
=> "  0.000000   0.000000   0.000000 (  2.000000)\n"
irb(main):007:0>

Cheers

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/