I'm trying to go through a file line-by-line and, if that line contains the hash key, I want to print the value. For example:
Months = { "January" => 1, "February" => 2, "March" => 3 } and if I have a file that contains:
February January March I want the output to be:
2 1 3 Can anyone give me some quick advice?
Assuming the following data structure:
data = 'Months = { "January" => 1, "February" => 2, "March" => 3 }' This will scan through it to find the numbers associated with the month names:
months_to_find = %w[January February March] months_re = Regexp.new( '(%s) .+ => \s+ (\d+)' % months_to_find.join('|'), Regexp::IGNORECASE | Regexp::EXTENDED ) Hash[*data.scan(months_re).flatten]['January'] # => 1 The magic occurs here:
months_re = Regexp.new( '(%s) .+ => \s+ (\d+)' % months_to_find.join('|'), Regexp::IGNORECASE | Regexp::EXTENDED ) which creates this regex:
/(January|February|March) .+ => \s+ (\d+)/ix Add additional months to months_to_find.
That will continue to work if the data is changed to:
data = 'Months = { "The month is January" => 1, "The month is February" => 2, "The month is March" => 3 }' months = { "January" => 1, "February" => 2, "March" => 3 } File.open('yourfile.txt').each_line do |line| result = months[line.strip] puts result if result end 
