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[No Audio]

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This tutorial is about some basic functions

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which are provided in the standard library

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for manipulating directory and path related

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functions, so let's start learning them.

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First I will bring the relevant modules into scope.

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[No Audio]

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First, we will cover some path related

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functions, I will create a path using the new

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function in the path module.

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[No Audio]

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The r before the text makes sure that the text is being

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treated as raw string, thereby escaping the

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effects of escape sequences. The parent

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function can be used to access the directory

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information in which a specific file is

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residing based on the path information of the

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file. Let us use this to display the directory

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in which the my_txt.txt file is residing.

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[No Audio]

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Please note that, it will return an option, so

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we have to unwrap it. Let us cargo run this now.

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[No Audio]

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Okay, great. To extract the file name, the

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module provides the file_stem

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function, and to access the extension of the

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file the module provides the extension

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function. Let us use them inside the print statement.

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[No Audio]

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Sometimes we may need to create our own path

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for arranging items in our own defined

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directory structure. We will create a PathBuf

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variable for this purpose. For instance,

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I want to create a new path for some files in the D drive.

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[No Audio]

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Next, I can add folders or sub directories to

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this path by simplifying using the push function.

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The final item will be the name of the file.

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[No Audio]

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Lastly, I will add the extension

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to path also by using the extension function.

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[No Audio]

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Let us print the full path now.

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[No Audio]

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Please note that although there are a couple of

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backslashes when we print the path, but this

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path is readable in Windows, and you can use it

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to create a file. The same can be done using

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iterators and vectors. First I will create a

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vector containing raw strings in sequential order.

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[No Audio]

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Next, I will iterate through all the elements

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using the iter function and then collect it

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in a PathBuf types.

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[No Audio]

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Finally, let us print the path.

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Let us cargo run this now.

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[No Audio]

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Both methods produces the same path.

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Sometimes it is useful to check if a

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certain directory exists in the file system

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or not, the is_directory function

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is used for this purpose. For instance, I will

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create a path variable first.

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[No Audio]

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Now to check if this path contains

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a valid directory on the system,

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I will use the is_dir function.

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[No Audio]

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Let us cargo run this now.

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Similar to the is directory, there is a function

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called is_file for checking if a

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certain, if a certain path is pointing to a

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valid file or not. Let us use it by first

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creating a path, that is pointing to a valid

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file on the system.

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Next, I will call the is_file

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function inside a print statement.

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Let us cargo run this now.

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The metadata is another useful function which

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provides the details of a file that is

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pointed to by the path variable, let us use it.

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[No Audio]

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This function returns a result enum, and

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therefore needs to unwrap to access its

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fields. The individual information about the

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file can be accessed using individual

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functions on the data. For instance, to

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display the file type, we will use the

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file _type function.

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[No Audio]

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Next we will display the

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bytes the file is taking in the memory,

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and the permissions and modified and created properties.

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[No Audio]

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Let us cargo run this now

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to see the details of the file.

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That was all for now related to the basic path

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related functions. This will cover majority

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of the needs that you may encounter during

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Rust programming. Let us now cover some of

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the directory related functions. First, I will

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comment out the code so far.

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[No Audio]

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The very first function we would like to

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learn is, to display all the files in a

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certain directory, I will first create a path variable.

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[No Audio]

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Next, we will use the read_dir

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function which enables us to loop through all

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the files. The read_dir directory

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returns a result with read directory

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structure, which contains the individual

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entries. When we iterate through this

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structure, it provides the individual

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directory entries. Finally, we use the expect

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function which will be called in case the

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read_dir call fails, which may

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happen when the directory does not exist in

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the memory. Inside the loop, I will display the files.

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We unwrapped the files as it is a result, and

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then use the path function to display the path

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of the file. Let us cargo run this now,

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to display all the paths.

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[No Audio]

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To display the current directory information,

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the environment module provides a function

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called current_directory. Let us

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use this to obtain the path of the current_dir.

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[No Audio]

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Let us also display the current

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path in a print statement.

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[No Audio]

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I will comment out the previous code before executing.

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[No Audio]

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Let us go go run this now.

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[No Audio]

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Next, we will learn how to create a directory. The

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create_dir function in the fs

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module will be used in this regards. I will

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create a new directory by calling the

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create_dir  function inside the print statement.

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[No Audio]

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This will create a new empty directory at

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the provided path. To create a directory and

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subdirectories inside them at the same time,

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we will use the create_dir_all

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function. Let us use it inside a print statement.

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[No Audio]

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Please note that, this will create a directory,

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and all its missing parents at the same time.

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This means that, since the level one was not

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created already, and which is a parent

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directory of the level two, so this function

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will create this also. However, since Rust

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one was already created, and it is also one of

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the parent directory, but since it already

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exists, so therefore it will not be created,

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let us cargo run this now.

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[No Audio]

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Both these function returns an Ok variant

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when the operation is successful. Let us

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inspect the D drive to see if the files have been created.

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[No Audio]

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You may note that we have rust1,

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what if we open it it contains the level1

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and then level2. Let us now move to the

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next topic, which is removing files and

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directories. First I will comment out the code so far.

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[No Audio]

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To remove a directory, there is a

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remove_dir function, this function

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can be used to remove a specific directory

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Let us use it inside the print statement.

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[No Audio]

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This function will not work, if the target

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directory contains some files or

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subdirectories. This means that it will only

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work if the target directory is empty and

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does not contain anything.

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[No Audio]

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For instance, if I call this function

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by providing the rust1

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directory, then it will not work.

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[No Audio]

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You may note that, the first call was

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successful, however the second call returned

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an error, because the directory was not empty.

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To forcefully delete everything from the

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directory, even if it contains some files or

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subdirectories, we will use the remove

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directory all function.

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[No Audio]

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This will erase all the directories

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even if it contains some

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items. Let us cargo run this.

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[No Audio]

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The last function in this regards is, to

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remove a specific file, the remove_file

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function will be used for this purpose.

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Let us use it inside a print statement to

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delete a file that we created earlier.

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[No Audio]

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The function rename can be used to rename a

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file. Let us explain its syntax in a print statement.

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[No Audio]

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Previous is the file for whom you

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want to change the name, and the new is the

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new name for the file. Please do not forget

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to provide the full name, along with the

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extension while renaming a file. The last

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operation in this tutorial is about copying

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the contents of one file to another. The copy

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function in the fs module is used for this

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purpose. Let us use it inside the print

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statement to elaborate its syntax.

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[No Audio]

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This will essentially copy the contents of the file

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new1.txt to new2.txt, deleting

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everything from new2 and , ill only contains

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the contents of the new1. That is it for

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this particular tutorial. See you again, and

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until then happy Rust programming.

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[No Audio]