Help Please!

Ruby
1

I’m new to Ruby, and have basically NO previous coding experience in any
other language.

What I’m trying to do is create a program that will run from cmd prompt,
and
let people type in words, or paragraphs etc., and then have those words
etc.
reversed.

Example:

This is my sentence => sentence my is This

Any help with this would be greatly appreciated!

2

On Jan 2, 2008, at 11:28 PM, 1up gfx wrote:

Example:

This is my sentence => sentence my is This

Any help with this would be greatly appreciated!

~> ruby -e ‘ARGF.each { |l| puts l.split.reverse.join( " " ) }’
this is my sentence
sentence my is this

Its a great answer to your assignment if you can explain what all is
happening. Good Luck!

Wes

3

From: “1up gfx” [email protected]

This is my sentence => sentence my is This

Any help with this would be greatly appreciated!

Do you have ri installed on your system?

ri is a program which can provide help with Ruby’s core
classes and methods.

Try (from your command prompt, not from IRB)

ri String#split

ri Array#reverse

ri Array#join

Hope this helps,

Bill

4

What I’m trying to do is create a program that will run from cmd prompt, and
let people type in words, or paragraphs etc., and then have those words etc.
reversed.

I can’t remember where exactly, but this is covered in at least one of
the basic tutorials (I know because I ran through them!). Do a google
search for “Ruby tutorial” and check some of those out.

If you can’t find it after searching let me know and I’ll try to track
it down.

5

On Thu, Jan 03, 2008 at 04:38:25PM +0900, Bill K. wrote:

reversed.
classes and methods.

Try (from your command prompt, not from IRB)

ri String#split

ri Array#reverse

ri Array#join

Also:

ri Kernel#gets

ri Kernel#puts

. . . and, aside from basic Ruby syntax, that might be everything you
need for the program.

6

On 1/2/08, 1up gfx [email protected] wrote:

Any help with this would be greatly appreciated!

First attempt:

[01-03 06:50] ~
! irb

gets.reverse
This is my sentence
=> “\necnetnes ym si sihT”

Second attempt:

[01-03 06:51] ~
! irb

got = gets
This is my sentence
=> “This is my sentence\n”
got.chomp! # remove the newline
=> “This is my sentence”
gots = got.split # turn it into an array
=> [“This”, “is”, “my”, “sentence”]
gots.reverse.join(" ") + “.” # reverse the array, join it with
spaces, add a dot
=> “sentence my is This.”

voila!

–
Giles B.

Podcast: http://hollywoodgrit.blogspot.com
Blog: http://gilesbowkett.blogspot.com
Portfolio: http://www.gilesgoatboy.org
Tumblelog: http://giles.tumblr.com

7

Oh that’s clever! I do believe you have honors on the next tee. :wink:

Wes

8

On Jan 3, 2008 10:53 AM, Joel VanderWerf [email protected]
wrote:

–
vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407

It doesn’t like your code… I keep on getting errors:

irb(main):001:0> puts $F.reverse.join(" ")
NoMethodError: undefined method `reverse’ for nil:NilClass
from (irb):1
irb(main):002:0>

9

Wes B. wrote:

~> ruby -e ‘ARGF.each { |l| puts l.split.reverse.join( " " ) }’
this is my sentence
sentence my is this

Golfing away…

$ ruby -ane ‘puts $F.reverse.join(" ")’
1 2 3
3 2 1

10

You don’t use irb for that. At the command prompt, that’s the ruby
command you give it.
$F = is an environmental variable that can receive split line input
as an array

a = autosplit mode, basically takes the input and splits it out
n = pauses the command, like assuming a “while” command
e = the command

regards,
ch0wda

11

On Jan 3, 2008 12:58 PM, Joshua S. [email protected]
wrote:

ch0wda

Golfing away…
irb(main):001:0> puts $F.reverse.join(" ")
NoMethodError: undefined method `reverse’ for nil:NilClass
from (irb):1
irb(main):002:0>

Alright, never mind, I got the program to work. Thank you for your help
guys!