Some String Handling - Ruby example

Strings and Regular Expressions example from a Well House Consultants training course
More on Strings and Regular Expressions [link]

This example is described in the following article(s):
• Ruby collections and strings - some new examples - [link]

Source code: bc Module: R109

# This example shows many of the string definition
# and handling options available to you in Ruby

# A "here" document - a block of text

about = <<'HEADER_END'
A Christmas tree has been dragged from Finland
to celebrate the birth of a child in Israel and
we are in England
HEADER_END

# Single quoted strings (and %q) are literals
# Double quoted strings (and %Q) are operators
# Back quoted strings (and %x) are OS commands

puts 'Hello World\n'
puts "Hello World\n"
puts %q!Hello 'World'\n!
puts %q(Hello 'World'\n)
puts %Q(Hello 'World'\n)
puts `uptime`
puts %x!df -k!
freespace = %x!df -k!

print about

# Split the df report line by line
lynes = freespace.split("\n")
p lynes

# remove the last and first lines
cd = lynes.pop
lynes.shift

# add a new line on the end
lynes.push("That's all folks")

# List out all the lines that are left
lynes.each do |here|
        puts here
        end

__END__

This is how it runs

92:d2 grahamellis$ ruby bc
Hello World\n
Hello World
Hello 'World'\n
Hello 'World'\n
Hello 'World'
19:51 up 1:49, 2 users, load averages: 1.62 0.86 0.66
Filesystem 1024-blocks Used Available Capacity Mounted on
/dev/disk0s3 117089712 108064516 8769196 93% /
devfs 119 119 0 100% /dev
fdesc 1 1 0 100% /dev
map -hosts 0 0 0 100% /net
map auto_home 0 0 0 100% /home
/dev/disk1 595064 595064 0 100%
        /Volumes/The No. 1 Summer Dance Hits Album [Disc 2]
A Christmas tree has been dragged from Finland
to celebrate the birth of a child in Israel and
we are in England
["Filesystem 1024-blocks Used Available Capacity Mounted on",
"/dev/disk0s3 117089712 108064516 8769196 93% /",
"devfs 119 119 0 100% /dev",
"fdesc 1 1 0 100% /dev",
"map -hosts 0 0 0 100% /net",
"map auto_home 0 0 0 100% /home",
"/dev/disk1 595064 595064 0 100%
        /Volumes/The No. 1 Summer Dance Hits Album [Disc 2]"]
/dev/disk0s3 117089712 108064516 8769196 93% /
devfs 119 119 0 100% /dev
fdesc 1 1 0 100% /dev
map -hosts 0 0 0 100% /net
map auto_home 0 0 0 100% /home
That's all folks
92:d2 grahamellis$

Learn about this subject

This module and example are covered on the following public courses:
* Learning to program in Ruby
* Ruby Programming
Also available on on site courses for larger groups

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