Ruby TYS

wtd · **Posted:** Thu Sep 29, 2005 6:51 pm

Let's kick it off with a challenge.

Given a file containing dates in the format:

code:

092203
072105
061704

That is read into an array called 'dates'.

code:

["092203", "072105", "061704"]

Create a new array called 'new_dates' with each date in the format: mm/dd/yy, rather than mmddyy.

Don't use regular expressions or slices. Smile

Cervantes · **Posted:** Fri Sep 30, 2005 9:17 pm

Ruby:

new_dates = File::open("dates.txt").readlines.collect { |d| d[0..1] + "/" +d[2..3] + "/" + d[4..5] }
p new_dates

Rather messy block I've got there. Sad

wtd · **Posted:** Sat Oct 01, 2005 1:58 pm

Cervantes wrote:

Ruby:

new_dates = File::open("dates.txt").readlines.collect { |d| d[0..1] + "/" +d[2..3] + "/" + d[4..5] }
p new_dates

Rather messy block I've got there. Sad

code:

d[0..1]

Is a slice. Smile

wtd · **Posted:** Fri Oct 28, 2005 5:46 pm

Write an HTTP server in at most 4 lines of code (no semi-colons) that sits on port 2000 and simply sends "Hello world!" to any clients that connect.

rdrake · **Posted:** Fri Nov 18, 2005 9:33 pm

wtd wrote:

Write an HTTP server in at most 4 lines of code (no semi-colons) that sits on port 2000 and simply sends "Hello world!" to any clients that connect.

Could only get it down to 5.

code:

require 'socket'

socket = TCPServer.new('127.0.0.1', 2000)
newSock = socket.accept
request = newSock.gets
newSock.print "HTTP/1.0 200 OK\r\nContent-type: text/plain\r\n\r\nHello World!\r\n"

Any way I can make it shorter?

wtd · **Posted:** Fri Nov 18, 2005 10:30 pm

Well, that kinda works. It only connects to one client, though. Smile

On removing extraneous code... this line doesn't serve any purpose.

code:

request = newSock.gets

rdrake · **Posted:** Sat Nov 19, 2005 11:11 am

wtd wrote:

Well, that kinda works. It only connects to one client, though. Smile

The following will connect with an unlimited number of clients, but it's over the limit.

code:

require 'socket'
socket = TCPServer.new('127.0.0.1', 2000)
while newSock = socket.accept
puts newSock.gets
newSock.print "HTTP/1.0 200 OK\r\nContent-type: text/html\r\n\r\n<html><head><title>Hello World!</title></head><body><p>Hello world!</p></body></html>\r\n"
newSock.close
end

wtd wrote:

On removing extraneous code... this line doesn't serve any purpose.

code:

request = newSock.gets

That line was there so browsers could connect to it too. After playing around with different telnet clients, I've managed to get the code down to this.

code:

require 'socket'
socket = TCPServer.new('127.0.0.1', 2000)
socket.accept
newSock.print "Hello world!"
newSock.close

Any ideas how I could get this down smaller?

wtd · **Posted:** Sat Nov 19, 2005 1:38 pm

Untested because I'm feeling lazy at the moment.

code:

require 'socket'

socket = TCPServer.new('127.0.0.1', 2000)
loop { Thread.start(server.accept) { |session| session.print "Hello world\n" } }

wtd · **Posted:** Wed Nov 23, 2005 8:14 pm

Create two classes "Foo" and "Bar". They should both implement "baz" and "put_baz" methods. The "baz" method should return a string. The "put_baz" method should print that string.

You may use the "def" keyword only three times and the class keyword only twice, and Foo and Bar may not share a common base class, other than Object.

Cervantes · **Posted:** Wed Nov 23, 2005 9:15 pm

Ruby:

module Bazzy
def baz
"Bazzy!"
end
def put_baz
puts baz
end
end

class Foo
include Bazzy
end

class Bar
include Bazzy
end

Foo.new.put_baz
Bar.new.put_baz

wtd · **Posted:** Wed Nov 23, 2005 9:21 pm

wtd wrote:

Let's kick it off with a challenge.

Given a file containing dates in the format:

code:

092203
072105
061704

That is read into an array called 'dates'.

code:

["092203", "072105", "061704"]

Create a new array called 'new_dates' with each date in the format: mm/dd/yy, rather than mmddyy.

Don't use regular expressions or slices. Smile

The answer:

code:

new_dates = dates.collect { |date| date.unpack("A2A2A2").join("/") }

wtd · **Posted:** Tue Nov 29, 2005 5:53 pm

code:

irb(main):006:0> class String
irb(main):007:1>
irb(main):008:2>
irb(main):009:2>
irb(main):010:1> end
=> nil
irb(main):011:0> "hello"
=> *****

Fill in the missing code. Smile

Note that with "hello" we get five stars. If one input "foo" on the next line, the result should be three stars.

wtd · **Posted:** Thu Dec 01, 2005 7:18 pm

code:

irb(main):001:0> a = Array.new(4, [])
=> [[], [], [], []]
irb(main):002:0> a[0] << 4
=> [4]
irb(main):003:0> a
=> [[4], [4], [4], [4]]

Rewrite the first line of code such that the third line yields:

code:

[[4], [], [], []]

You may only remove one character, and add two others.

wtd · **Posted:** Mon Dec 05, 2005 1:23 pm

wtd wrote:

code:

irb(main):006:0> class String
irb(main):007:1> def inspect
irb(main):008:2> '*' * length
irb(main):009:2> end
irb(main):010:1> end
=> nil
irb(main):011:0> "hello"
=> *****

Fill in the missing code. Smile

Note that with "hello" we get five stars. If one input "foo" on the next line, the result should be three stars.

wtd · **Posted:** Mon Dec 05, 2005 1:24 pm

wtd wrote:

code:

irb(main):001:0> a = Array.new(4, [])
=> [[], [], [], []]
irb(main):002:0> a[0] << 4
=> [4]
irb(main):003:0> a
=> [[4], [4], [4], [4]]

Rewrite the first line of code such that the third line yields:

code:

[[4], [], [], []]

You may only remove one character, and add two others.

code:

irb(main):001:0> a = Array.new(4) { [] }
=> [[], [], [], []]
irb(main):002:0> a[0] << 4
=> [4]
irb(main):003:0> a
=> [[4], [], [], []]

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