Ruby vs Python vs Perl (programming example)

[Laura Raffa]

Hi,

I have no experience with Ruby, but there is currently a debate in the
office about Python over Perl, Java, C++ etc. It's a simple programming
example:

find and print all words ending with some predefined suffix

An array of words can be assumed. The shortest possible code solution (and
also the most elegant) is required. A Perl solution with the -n option was
disallowed.

As I don't know Ruby, can anyone give me a quick example. The Ruby guy who
rabbits on about the excellence of Ruby isn't here to day. Thought I'd
check.


Thanks

 

[Assaph Mehr]

find and print all words ending with some predefined suffix

An array of words can be assumed. The shortest possible code solution (and
also the most elegant) is required. A Perl solution with the -n option was
disallowed.

Assume:
.. words = [...] # array
.. suffix = "..." # string

Then:
.. puts words.select { |word| word =~ /#{suffix}$/ }

 

[Dave Burt]

Hi,

I have no experience with Ruby, but there is currently a debate in the
office about Python over Perl, Java, C++ etc. It's a simple programming
example:

find and print all words ending with some predefined suffix

An array of words can be assumed. The shortest possible code solution (and
also the most elegant) is required. A Perl solution with the -n option was
disallowed.

Ruby:
puts words.select { |word| /#{suffix}$/ =~ word }
or
words.each {|word| puts word if /#{suffix}$/ =~ word }
or
for word in words
puts word if /#{suffix}$/ =~ word
end

Perl:
print grep /$suffix$/, @words;
or
for (@words) { print if /$suffix$/ }

I think I prefer Perl's solution for such a trivial example. You're only
going to see the superiority of Ruby over Perl in a bigger problem, so you
can crack out your elegant class definitions and reflection and general
dynamism, and watch the Perl hacker fight with references and {$%@#/&***/\

Cheers,
Dave

 

[Csaba Henk]

find and print all words ending with some predefined suffix

An array of words can be assumed. The shortest possible code solution (and
also the most elegant) is required. A Perl solution with the -n option was
disallowed.

Assume:
. words = [...] # array
. suffix = "..." # string

Then:
. puts words.select { |word| word =~ /#{suffix}$/ }

Maybe /#{Regexp.quote suffix}$/, if you want to be general...

Csaba

 

[gabriele renzi]

Assaph Mehr ha scritto:

find and print all words ending with some predefined suffix

An array of words can be assumed. The shortest possible code solution
(and

also the most elegant) is required. A Perl solution with the -n

option was

disallowed.

Assume:
. words = [...] # array
. suffix = "..." # string

Then:
. puts words.select { |word| word =~ /#{suffix}$/ }

for String there is a special method of Enumerable, since this is an
important case:
puts words.grep(/suffix$/)

 

[Dave Burt]

Assaph Mehr ha scritto:

for String there is a special method of Enumerable, since this is an
important case:
puts words.grep(/suffix$/)

Cool! It's not a special case, it's a case-equality match:

-------------------------------------------------------- Enumerable#grep
enum.grep(pattern) => array
enum.grep(pattern) {| obj | block } => array
------------------------------------------------------------------------
Returns an array of every element in _enum_ for which +Pattern ===
element+. If the optional _block_ is supplied, each matching
element is passed to it, and the block's result is stored in the
output array.

a = [nil, 1, 3.5, 'a', nil, 10**100, [], {}, 'b', 'c']
a.grep(NilClass).size #=> 2
a.grep(String) #=> ['a', 'b', 'c']
a.grep(Numeric) #=> [1, 3.5, 10000...]

So you can do regex-matches on string arrays, and kind_of?-matches, and
equality-matches.

Cheers,
Dave

 

[Pit Capitain]

find and print all words ending with some predefined suffix

puts words.grep(/#{suffix}$/)

Regards,
Pit

 

[gabriele renzi]

Dave Burt ha scritto:

Cool! It's not a special case, it's a case-equality match:

Well, I think that is the generalization of the special case
as the name suggest, I think it was initially done for finding strings

 

[Guyver2]

Hi,

I have no experience with Ruby, but there is currently a debate in the
office about Python over Perl, Java, C++ etc. It's a simple programming
example:

find and print all words ending with some predefined suffix

An array of words can be assumed. The shortest possible code solution (and
also the most elegant) is required. A Perl solution with the -n option was
disallowed.

As I don't know Ruby, can anyone give me a quick example. The Ruby guy who
rabbits on about the excellence of Ruby isn't here to day. Thought I'd
check.


Thanks

http://www.approximity.com/ruby/Comparison_rb_st_m_java.html
http://www.angelfire.com/tx4/cus/shapes/

 

[Kristof Bastiaensen]

puts words.grep(/#{suffix}$/)

Regards,
Pit

Nice. If suffix contains regexp characters it is safer to quote them:

puts words.grep(/#{Regexp.quote(suffix)}$/)

Regards,
KB

 

[gene.tani]

http://www.ruby-doc.org/RubyEyeForThePythonGuy.html

and the appendices "Perl vs. Ruby" and "Python vs. Ruby" in the back of
Hal Fulton "Ruby Way" book.

 

[BearItAll]

Hi,

I have no experience with Ruby, but there is currently a debate in the
office about Python over Perl, Java, C++ etc. It's a simple programming
example:

find and print all words ending with some predefined suffix

An array of words can be assumed. The shortest possible code solution (and
also the most elegant) is required. A Perl solution with the -n option was
disallowed.

As I don't know Ruby, can anyone give me a quick example. The Ruby guy who
rabbits on about the excellence of Ruby isn't here to day. Thought I'd
check.


Thanks

I don't see why perl should wear a handycap.