From: Mike Stok <mike@...>
Date: 2001-02-06T12:15:26+09:00
Subject: [ruby-talk:10396] Re: [OT now] Re: Structured text matching?

On Tue, 6 Feb 2001, Michael Schuerig wrote:

> Very interesting! I've never looked into Parse::RecDescent, but after a
> quick glimpse over an article by Randal Schwartz, it's pretty
> impressive.

Damian Conway does a lot of impressive stuff and useful stuff in perl,
e.g. Getopt::Declare, Parse::RecDescent, ways to do classless OO in perl,
wats to do programming by contract in perl, etc.  But it's the plain
amazing stuff which makes me smile:

In the Ruby examples directory I find sieve.rb which is elegant in its
way:

# sieve of Eratosthenes
max = Integer(ARGV.shift || 100)
sieve = []
for i in 2 .. max
  sieve[i] = i
end

for i in 2 .. Math.sqrt(max)
  next unless sieve[i]
  (i*i).step(max, i) do |j|
    sieve[j] = nil
  end
end
puts sieve.compact.join ", "

[mike@ratdog sample]$ ruby sieve.rb 10
2, 3, 5, 7

and in /usr/local/src/perl/modules/Lingua-Romana-Perligata-0.01/demo I
find demo_eratosthenes.pl which is elegant in its expression, if not its
algorithm:

use Lingua::Romana::Perligata
# 'converte',
# 'discribe'
# 'investiga',
;

maximum tum val inquementum tum biguttam tum stadium egresso scribe.
vestibulo perlegementum da meo maximo .
maximum tum novumversum egresso scribe.
da II tum maximum conscribementa meis listis.
dum damentum nexto listis decapitamentum fac sic
       lista sic hoc tum nextum recidementum  cis vannementa da listis.
       next tum biguttam tum stadium tum nextum tum novumversum scribe egresso.
    cis

[builder@ratdog demo]$ perl demo_eratosthenes.pl
maximum val:    10
10

next:   2
next:   3
next:   5
next:   7

See http://www.csse.monash.edu.au/~damian/papers/HTML/Perligata.html for
an explanation.  If you ever get a chance to catch Damian's talks then do.

Sorry for the off topic post.

Mike

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