Step by Step solution about How to resolve the algorithm Walk a directory/Non-recursively step by step in the Ruby programming language

The given Ruby code demonstrates how to use the Dir.glob method to find and list files in a directory or specified path. Here's a detailed breakdown of the code:

1. Dir.glob('*'):

   • This line uses the Dir.glob method to find all files in the current directory (the directory where the Ruby script is being executed).
   • The asterisk (*) in the argument represents a wildcard, meaning it matches any file.

2. Dir.glob( File.join('/foo/bar', '*') ):

   • This line uses Dir.glob to find all files in the '/foo/bar' directory.
   • File.join('/foo/bar', '*') joins the path '/foo/bar' with the wildcard '*' to create a pattern that matches any file in that directory.

3. def file_match(pattern=/\.txt/, path='.'):

   • This line defines a method named file_match that takes two optional parameters:
     • pattern: A regular expression used to match files based on their names. The default value is /\.txt/, which matches files ending with .txt.
     • path: The path to the directory to search. The default value is '.', which represents the current directory.

4. Dir[File.join(path,'*')].each do |file|:

   • This line uses the Dir[] syntax to create an array of files that match the specified pattern and path.
   • It joins the path with the wildcard '*' to create a pattern that matches any file in the given directory.
   • The each method iterates through each file in the array.

5. puts file if file =~ pattern:

   • Inside the loop, this line checks if the current file matches the specified pattern using the regular expression comparison file =~ pattern.
   • If there is a match, it prints the name of the file using puts.

In summary, this code provides two ways to list files in a directory or specified path. It demonstrates how to use Dir.glob directly and through a custom file_match method to filter files based on a pattern.

# Files under this directory:
Dir.glob('*') { |file| puts file }

# Files under path '/foo/bar':
Dir.glob( File.join('/foo/bar', '*') ) { |file| puts file }

# As a method
def file_match(pattern=/\.txt/, path='.')
  Dir[File.join(path,'*')].each do |file|
    puts file if file =~ pattern
  end
end