CODEWITHSUNDEEP
rubyarrays
blue-sky
blue-sky

Reputation: 53806

Comparing two variables

Am I comparing the pipe symbols |x| & |f| correctly below ?

|f| corresponds to the name of a dir |x| corresponds to the name of a file

  Dir.foreach(@sortedFilesDir) do
  |f|
    @fileArray.each() {
      |x| 
      if(x.match(/^#{f}/))
        puts "match - "+x+","+f
      end
    }
  end

Upvotes: 1

Views: 257

Answers (2)

Andrew Grimm
Andrew Grimm

Reputation: 81510

I've made a few changes:

  1. I made the variable names more informative
  2. I replaced the regular expression with String#start_with?
  3. I made the code more functional-programming than imperative programming, by replacing two eachs with a map and a find.
  4. I used "#{expression}" rather than "match - "+x+","+f

I haven't checked that it works, though.

directory_names = Dir.foreach(@sorted_files_dir)
matching_directory_names = @file_array.map do |filename|
  directory_names.find do |directory_name|
    filename.start_with?("/" + filename + "/")
  end
end
@file_array.zip(matching_directory_names) do |filename, matching_directory_name|
  next if matching_directory_name.nil?
  puts "match - #{filename},#{matching_directory_name}"
end

I hope directory_names doesn't get calculated every time the loop gets run! If it does, then you might want directory_names = Dir.foreach(@sorted_files_dir).to_a at the start of the script.

Upvotes: 1

Gazler
Gazler

Reputation: 84150

It is the general convention that you use the do |var| notation if your block is more than 1 line. If it is 1 line, use the {|var|} syntax.

String interpolation is also preferred to concatenation as it uses less methods.

Another convention is that if your method doesn't take arguments, don't use the brackets at the end. (Like you have done in your each method)

Also, in the ruby world, we usually underscore_our_variable_names instead of camelCasing them. The exception being Constants (including class names) e.g. MyClass or ThisIsOneOfMyConstants

 Dir.foreach(@sorted_files) do |f|
    @file_array.each do |x| 
      if(x.match(/^#{f}/))
        puts "match - #{x},#{f}"
      end
    end
  end

You are using them correctly if your goal is to list files in the specified directory that match an entry in your @file_array.

Upvotes: 1

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