# Different Ways To Loop

I love the flexibility of Ruby. It gives you several ways to do
something, leaving you to pick the most appropriate one. In the
spirit of showing off the flexibility of Ruby, I’d like to see how
many different ways there are to write a loop that prints the numbers
1 to 100, one on each line. I’ll start off:

1.upto(100) { |x| puts x }

I know there’s at least a dozen more ways to do this…

From: “Wyatt G.” [email protected]

1.upto(100) { |x| puts x }

Ruby can even do the looping on our behalf.

puts (1…100).to_a

Regards,

Bill

Wyatt G. wrote:

I love the flexibility of Ruby. It gives you several ways to do
something, leaving you to pick the most appropriate one. In the
spirit of showing off the flexibility of Ruby, I’d like to see how
many different ways there are to write a loop that prints the numbers
1 to 100, one on each line. I’ll start off:

1.upto(100) { |x| puts x }

I know there’s at least a dozen more ways to do this…

100.times {|x| puts x + 1}
(1…100).to_a.each {|x| puts x}

Quoting Linux D. [email protected]:

## 100.times {|x| puts x + 1} (1…100).to_a.each {|x| puts x}

Posted via http://www.ruby-forum.com/.

You don’t even need the to_a part

(1…100).each { |x| p x }

On May 3, 10:24 pm, Linux D. [email protected] wrote:

## 100.times {|x| puts x + 1} (1…100).to_a.each {|x| puts x}

Posted viahttp://www.ruby-forum.com/.

p *1…100

On May 3, 10:27 pm, [email protected] wrote:

(1…100).each { |x| p x }

count = 1; loop { puts count; count += 1; break if count > 100; }

On May 3, 2008, at 8:10 PM, Wyatt G. wrote:

1.upto(100) { |x| puts x }

here are a few

# 1

puts Array.new(100){|i| i + 1}

# 2

i = 0 and loop do
puts i+=1
break if i >= 100
end

# 3

puts <<-chars.strip.split(%r//).map{|c| c[0]}
\001\002\003\004\005\006\a\b\t\n\v\f\r
\016\017\020\021\022\023\024\025\026\027\030\031\032\e\034\035\036\037!
"#\$%&’()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcd
chars

# 4

100.times{|i| puts i + 1}

Don’t forget the “traditional” style loop:

for x in 1…100 do
puts x+1
end

of course there’s…

i=0 and while(i<100) do
puts i+=1
end

i=0 and until(i==100) do
puts i+=1
end

On Sat, May 3, 2008 at 11:48 PM, Dan Z. [email protected] wrote:

On May 3, 2008, at 8:10 PM, Wyatt G. wrote:

# 2

Aloha!

Mike McKinney
[email protected]
(http://blog.huikau.com)

On Sun, May 4, 2008 at 8:55 AM, Wyatt G. [email protected] wrote:

puts i+=1

def count
Based on a response from Eric when I first asked for alternative ways to
do this:

MAX = 100
def print_from_to(start, stop)
start.upto(stop) do |number|
puts number
end
end
loop do
number = 1
print_from_to(number, MAX)
break
end

On May 4, 1:54 am, Mike McKinney [email protected] wrote:

end

ara.t.howard wrote:

# 2

Aloha!

Mike McKinney
[email protected]
(http://blog.huikau.com)

And here’s an “object-oriented” way:

class Counter
def count
@count ||= 1
puts @count
@count += 1
@count > 100
end
end

counter = Counter.new
until counter.count; end

Hi –

On Sun, 4 May 2008, Ashley W. wrote:

puts x+1

# 1

better. simply reflect on that.

until counter.count; end
loop do
number = 1
print_from_to(number, MAX)
break
end

I can think of lots of ways:

puts *1…100
puts *1…101-1
puts *1…102-2 …

or

“This evaluates to true” and loop do …

“So does this” and loop do …

I don’t mean to scoff at the “more than one way” thing, but it does
in a sense contain the seeds of its own destruction

David

On May 4, 3:22 pm, Ken B. [email protected] wrote:

([nil]*100).each_with_index{|,i| puts i+1}
Array.new(100).each_with_index{|
,i| puts i+1}

Ken (Chanoch) Bloom. PhD candidate. Linguistic Cognition Laboratory.
Department of Computer Science. Illinois Institute of Technology.http://www.iit.edu/~kbloom1/

Nice ones, Ken!

Here’s another one, lifted from page 128 of “The Ruby P.ming
Language”:

x = 10
puts x = x + 1 while x < 100

2008/5/4 Wyatt G. [email protected]:

I love the flexibility of Ruby. It gives you several ways to do
something, leaving you to pick the most appropriate one. In the
spirit of showing off the flexibility of Ruby, I’d like to see how
many different ways there are to write a loop that prints the numbers
1 to 100, one on each line. I’ll start off:

1.upto(100) { |x| puts x }

I know there’s at least a dozen more ways to do this…

I haven’t seen ‘retry’ so far:

10:48:13 RTEConnector\$ ruby -e ‘i=0;begin;puts i;raise
“X”;rescue;i+=1;retry if i<=10;end’
0
1
2
3
4
5
6
7
8
9
10
10:48:25 RTEConnector\$

Cheers

robert

On Sat, 03 May 2008 19:07:12 -0700, Wyatt G. wrote:

I love the flexibility of Ruby. It gives you several ways to do
something, leaving you to pick the most appropriate one. In the spirit
of showing off the flexibility of Ruby, I’d like to see how many
different ways there are to write a loop that prints the numbers 1 to
100, one on each line. I’ll start off:

1.upto(100) { |x| puts x }

I know there’s at least a dozen more ways to do this…

([nil]*100).each_with_index{|,i| puts i+1}
Array.new(100).each_with_index{|
,i| puts i+1}

Hmm, the example with p *1…100 surprised me, I knew the * but I somehow
havent seen this used in such a short way

I guess fun examples would be that noone notices that a loop is a
work… isn’t there an obfuscated way with Array(pack/unpack)?

Hi –

On Mon, 5 May 2008, Marc H. wrote:

Hmm, the example with p *1…100 surprised me, I knew the * but I somehow
havent seen this used in such a short way

I guess fun examples would be that noone notices that a loop is a
work… isn’t there an obfuscated way with Array(pack/unpack)?

I think there are infinite obfuscated ways. It depends what you
consider a “way” to print the integers 1 to 100. You can surround it
with unintelligible garbage, encrypt it and then unencrypt and eval
it, and so forth.

It’s an interesting question: what’s the horizon of a “way” to do
something, using “way” as in “Ruby gives you different ways to do
xyz”? I don’t believe that the relation between, say, p *1…100 and
puts [1,2,3,…,100] is the same as the relation between either of
those ways of printing integers and

puts [eval(“1” + (("\$%#\$&."[-1,1]) * 2) +
((212-32)5/9).to_s)].pack(%{#{"".class.class.name[0].chr}}).unpack("#{‘B’.succ}*")

or whatever. That prints the numbers but I don’t think it can usefully
be described as a “way” to print an array of integers.

David

Different Ways To Loop

Posted by Wyatt G. (Guest) on 04.05.2008 04:10

I love the flexibility of Ruby. It gives you several ways to do
something, leaving you to pick the most appropriate one. In the
spirit of showing off the flexibility of Ruby, I’d like to see how
many different ways there are to write a loop that prints the numbers
1 to 100, one on each line. …

Just for the sake of completeness!

puts Array(1…100)

Cheers,

j.k.

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