Step by Step solution about How to resolve the algorithm Walk a directory/Recursively step by step in the Julia programming language

This code is written in Julia programming language, and it is used to find all the files with a specific extension in a given directory. The code receives two parameters: the root path and a pattern to match the files.

The first line of the code creates a variable rootpath and assigns it the value of the root path. The second line creates a variable pattern and assigns it the value of the regular expression pattern to match the files.

The third line of the code uses the walkdir function to iterate over the files and directories in the root path. The walkdir function takes the root path as a parameter and returns a tuple of three elements: the root path, a list of directories, and a list of files.

The fourth line of the code uses a for loop to iterate over the files in the root path. The fifth line of the code uses the occursin function to check if the pattern matches the file. If the pattern matches the file, the sixth line of the code prints the file name.

Here is an example of how the code would work:

julia> rootpath = "/home/user/music"
julia> pattern = r".mp3$"

julia> for (root, dirs, files) in walkdir(rootpath)
          for file in files
              if occursin(pattern, file) println(file) end
          end
      end

/home/user/music/song1.mp3
/home/user/music/song2.mp3
/home/user/music/song3.mp3

In this example, the rootpath variable is set to the directory /home/user/music. The pattern variable is set to the regular expression pattern r".mp3$", which matches all the files that have the .mp3 extension.

The walkdir function is used to iterate over the files and directories in the root path. The for loop iterates over the files in the root path. The occursin function is used to check if the pattern matches the file. If the pattern matches the file, the println function prints the file name.

The output of the code is a list of all the files in the root path that have the .mp3 extension.

rootpath = "/home/user/music"
pattern  = r".mp3$"

for (root, dirs, files) in walkdir(rootpath)
    for file in files
        if occursin(pattern, file) println(file) end
    end
end