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Struct async_std::path::Path

source · [−]
pub struct Path { /* private fields */ }
Expand description

A slice of a path.

This struct is an async version of std::path::Path.

This type supports a number of operations for inspecting a path, including breaking the path into its components (separated by / on Unix and by either / or \ on Windows), extracting the file name, determining whether the path is absolute, and so on.

This is an unsized type, meaning that it must always be used behind a pointer like & or Box. For an owned version of this type, see PathBuf.

More details about the overall approach can be found in the module documentation.

Examples

use std::path::Path;
use std::ffi::OsStr;

// Note: this example does work on Windows
let path = Path::new("./foo/bar.txt");

let parent = path.parent();
assert_eq!(parent, Some(Path::new("./foo")));

let file_stem = path.file_stem();
assert_eq!(file_stem, Some(OsStr::new("bar")));

let extension = path.extension();
assert_eq!(extension, Some(OsStr::new("txt")));

Implementations

Directly wraps a string slice as a Path slice.

This is a cost-free conversion.

Examples
use async_std::path::Path;

Path::new("foo.txt");

You can create Paths from Strings, or even other Paths:

use async_std::path::Path;

let string = String::from("foo.txt");
let from_string = Path::new(&string);
let from_path = Path::new(&from_string);
assert_eq!(from_string, from_path);

Returns the underlying OsStr slice.

Examples
use std::ffi::OsStr;

use async_std::path::Path;

let os_str = Path::new("foo.txt").as_os_str();
assert_eq!(os_str, OsStr::new("foo.txt"));

Returns a &str slice if the Path is valid unicode.

This conversion may entail doing a check for UTF-8 validity. Note that validation is performed because non-UTF-8 strings are perfectly valid for some OS.

Examples
use async_std::path::Path;

let path = Path::new("foo.txt");
assert_eq!(path.to_str(), Some("foo.txt"));

Converts a Path to a Cow<str>.

Any non-Unicode sequences are replaced with U+FFFD REPLACEMENT CHARACTER.

Examples

Calling to_string_lossy on a Path with valid unicode:

use async_std::path::Path;

let path = Path::new("foo.txt");
assert_eq!(path.to_string_lossy(), "foo.txt");

Had path contained invalid unicode, the to_string_lossy call might have returned "fo�.txt".

Converts a Path to an owned PathBuf.

Examples
use async_std::path::{Path, PathBuf};

let path_buf = Path::new("foo.txt").to_path_buf();
assert_eq!(path_buf, PathBuf::from("foo.txt"));

Returns true if the Path is absolute, i.e. if it is independent of the current directory.

  • On Unix, a path is absolute if it starts with the root, so is_absolute and has_root are equivalent.

  • On Windows, a path is absolute if it has a prefix and starts with the root: c:\windows is absolute, while c:temp and \temp are not.

Examples
use async_std::path::Path;

assert!(!Path::new("foo.txt").is_absolute());

Returns true if the Path is relative, i.e. not absolute.

See is_absolute’s documentation for more details.

Examples
use async_std::path::Path;

assert!(Path::new("foo.txt").is_relative());

Returns true if the Path has a root.

  • On Unix, a path has a root if it begins with /.

  • On Windows, a path has a root if it:

    • has no prefix and begins with a separator, e.g. \windows
    • has a prefix followed by a separator, e.g. c:\windows but not c:windows
    • has any non-disk prefix, e.g. \\server\share
Examples
use async_std::path::Path;

assert!(Path::new("/etc/passwd").has_root());

Returns the Path without its final component, if there is one.

Returns None if the path terminates in a root or prefix.

Examples
use async_std::path::Path;

let path = Path::new("/foo/bar");
let parent = path.parent().unwrap();
assert_eq!(parent, Path::new("/foo"));

let grand_parent = parent.parent().unwrap();
assert_eq!(grand_parent, Path::new("/"));
assert_eq!(grand_parent.parent(), None);

Produces an iterator over Path and its ancestors.

The iterator will yield the Path that is returned if the parent method is used zero or more times. That means, the iterator will yield &self, &self.parent().unwrap(), &self.parent().unwrap().parent().unwrap() and so on. If the parent method returns None, the iterator will do likewise. The iterator will always yield at least one value, namely &self.

Examples
use async_std::path::Path;

let mut ancestors = Path::new("/foo/bar").ancestors();
assert_eq!(ancestors.next(), Some(Path::new("/foo/bar").into()));
assert_eq!(ancestors.next(), Some(Path::new("/foo").into()));
assert_eq!(ancestors.next(), Some(Path::new("/").into()));
assert_eq!(ancestors.next(), None);

Returns the final component of the Path, if there is one.

If the path is a normal file, this is the file name. If it’s the path of a directory, this is the directory name.

Returns None if the path terminates in ...

Examples
use std::ffi::OsStr;

use async_std::path::Path;

assert_eq!(Some(OsStr::new("bin")), Path::new("/usr/bin/").file_name());
assert_eq!(Some(OsStr::new("foo.txt")), Path::new("tmp/foo.txt").file_name());
assert_eq!(Some(OsStr::new("foo.txt")), Path::new("foo.txt/.").file_name());
assert_eq!(Some(OsStr::new("foo.txt")), Path::new("foo.txt/.//").file_name());
assert_eq!(None, Path::new("foo.txt/..").file_name());
assert_eq!(None, Path::new("/").file_name());

Returns a path that becomes self when joined onto base.

Errors

If base is not a prefix of self (i.e., starts_with returns false), returns Err.

Examples
use async_std::path::{Path, PathBuf};

let path = Path::new("/test/haha/foo.txt");

assert_eq!(path.strip_prefix("/"), Ok(Path::new("test/haha/foo.txt")));
assert_eq!(path.strip_prefix("/test"), Ok(Path::new("haha/foo.txt")));
assert_eq!(path.strip_prefix("/test/"), Ok(Path::new("haha/foo.txt")));
assert_eq!(path.strip_prefix("/test/haha/foo.txt"), Ok(Path::new("")));
assert_eq!(path.strip_prefix("/test/haha/foo.txt/"), Ok(Path::new("")));
assert_eq!(path.strip_prefix("test").is_ok(), false);
assert_eq!(path.strip_prefix("/haha").is_ok(), false);

let prefix = PathBuf::from("/test/");
assert_eq!(path.strip_prefix(prefix), Ok(Path::new("haha/foo.txt")));

Determines whether base is a prefix of self.

Only considers whole path components to match.

Examples
use async_std::path::Path;

let path = Path::new("/etc/passwd");

assert!(path.starts_with("/etc"));
assert!(path.starts_with("/etc/"));
assert!(path.starts_with("/etc/passwd"));
assert!(path.starts_with("/etc/passwd/"));

assert!(!path.starts_with("/e"));

Determines whether child is a suffix of self.

Only considers whole path components to match.

Examples
use async_std::path::Path;

let path = Path::new("/etc/passwd");

assert!(path.ends_with("passwd"));

Extracts the stem (non-extension) portion of file_name.

The stem is:

  • None, if there is no file name
  • The entire file name if there is no embedded .
  • The entire file name if the file name begins with . and has no other .s within
  • Otherwise, the portion of the file name before the final .
Examples
use async_std::path::Path;

let path = Path::new("foo.rs");

assert_eq!("foo", path.file_stem().unwrap());

Extracts the extension of file_name, if possible.

The extension is:

  • None, if there is no file name
  • None, if there is no embedded .
  • None, if the file name begins with . and has no other .s within
  • Otherwise, the portion of the file name after the final .
Examples
use async_std::path::Path;

let path = Path::new("foo.rs");

assert_eq!("rs", path.extension().unwrap());

Creates an owned PathBuf with path adjoined to self.

See PathBuf::push for more details on what it means to adjoin a path.

Examples
use async_std::path::{Path, PathBuf};

assert_eq!(Path::new("/etc").join("passwd"), PathBuf::from("/etc/passwd"));

Creates an owned PathBuf like self but with the given file name.

See PathBuf::set_file_name for more details.

Examples
use async_std::path::{Path, PathBuf};

let path = Path::new("/tmp/foo.txt");
assert_eq!(path.with_file_name("bar.txt"), PathBuf::from("/tmp/bar.txt"));

let path = Path::new("/tmp");
assert_eq!(path.with_file_name("var"), PathBuf::from("/var"));

Creates an owned PathBuf like self but with the given extension.

See PathBuf::set_extension for more details.

Examples
use async_std::path::{Path, PathBuf};

let path = Path::new("foo.rs");
assert_eq!(path.with_extension("txt"), PathBuf::from("foo.txt"));

Produces an iterator over the Components of the path.

When parsing the path, there is a small amount of normalization:

  • Repeated separators are ignored, so a/b and a//b both have a and b as components.

  • Occurrences of . are normalized away, except if they are at the beginning of the path. For example, a/./b, a/b/, a/b/. and a/b all have a and b as components, but ./a/b starts with an additional CurDir component.

  • A trailing slash is normalized away, /a/b and /a/b/ are equivalent.

Note that no other normalization takes place; in particular, a/c and a/b/../c are distinct, to account for the possibility that b is a symbolic link (so its parent isn’t a).

Examples
use std::ffi::OsStr;

use async_std::path::{Path, Component};

let mut components = Path::new("/tmp/foo.txt").components();

assert_eq!(components.next(), Some(Component::RootDir));
assert_eq!(components.next(), Some(Component::Normal(OsStr::new("tmp"))));
assert_eq!(components.next(), Some(Component::Normal(OsStr::new("foo.txt"))));
assert_eq!(components.next(), None);

Produces an iterator over the path’s components viewed as OsStr slices.

For more information about the particulars of how the path is separated into components, see components.

Examples
use std::ffi::OsStr;

use async_std::path::{self, Path};

let mut it = Path::new("/tmp/foo.txt").iter();
assert_eq!(it.next(), Some(OsStr::new(&path::MAIN_SEPARATOR.to_string())));
assert_eq!(it.next(), Some(OsStr::new("tmp")));
assert_eq!(it.next(), Some(OsStr::new("foo.txt")));
assert_eq!(it.next(), None)

Returns an object that implements Display for safely printing paths that may contain non-Unicode data.

Examples
use async_std::path::Path;

let path = Path::new("/tmp/foo.rs");

println!("{}", path.display());

Reads the metadata of a file or directory.

This function will traverse symbolic links to query information about the destination file.

This is an alias to fs::metadata.

Examples
use async_std::path::Path;

let path = Path::new("/Minas/tirith");
let metadata = path.metadata().await?;
println!("{:?}", metadata.file_type());

Reads the metadata of a file or directory without following symbolic links.

This is an alias to fs::symlink_metadata.

Examples
use async_std::path::Path;

let path = Path::new("/Minas/tirith");
let metadata = path.symlink_metadata().await?;
println!("{:?}", metadata.file_type());

Returns the canonical form of a path.

The returned path is in absolute form with all intermediate components normalized and symbolic links resolved.

This is an alias to fs::canonicalize.

Examples
use async_std::path::{Path, PathBuf};

let path = Path::new("/foo/test/../test/bar.rs");
assert_eq!(path.canonicalize().await?, PathBuf::from("/foo/test/bar.rs"));

Reads a symbolic link, returning the file that the link points to.

This is an alias to fs::read_link.

Examples
use async_std::path::Path;

let path = Path::new("/laputa/sky_castle.rs");
let path_link = path.read_link().await?;

Returns a stream over the entries within a directory.

The stream will yield instances of io::Result<DirEntry>. New errors may be encountered after an iterator is initially constructed.

This is an alias to fs::read_dir.

Examples
use async_std::fs;
use async_std::path::Path;
use async_std::prelude::*;

let path = Path::new("/laputa");
let mut dir = fs::read_dir(&path).await?;

while let Some(res) = dir.next().await {
    let entry = res?;
    println!("{}", entry.file_name().to_string_lossy());
}

Returns true if the path points at an existing entity.

This function will traverse symbolic links to query information about the destination file. In case of broken symbolic links this will return false.

If you cannot access the directory containing the file, e.g., because of a permission error, this will return false.

Examples
use async_std::path::Path;
assert_eq!(Path::new("does_not_exist.txt").exists().await, false);
See Also

This is a convenience function that coerces errors to false. If you want to check errors, call fs::metadata.

Returns true if the path exists on disk and is pointing at a regular file.

This function will traverse symbolic links to query information about the destination file. In case of broken symbolic links this will return false.

If you cannot access the directory containing the file, e.g., because of a permission error, this will return false.

Examples
use async_std::path::Path;
assert_eq!(Path::new("./is_a_directory/").is_file().await, false);
assert_eq!(Path::new("a_file.txt").is_file().await, true);
See Also

This is a convenience function that coerces errors to false. If you want to check errors, call fs::metadata and handle its Result. Then call fs::Metadata::is_file if it was Ok.

Returns true if the path exists on disk and is pointing at a directory.

This function will traverse symbolic links to query information about the destination file. In case of broken symbolic links this will return false.

If you cannot access the directory containing the file, e.g., because of a permission error, this will return false.

Examples
use async_std::path::Path;

assert_eq!(Path::new("./is_a_directory/").is_dir().await, true);
assert_eq!(Path::new("a_file.txt").is_dir().await, false);
See Also

This is a convenience function that coerces errors to false. If you want to check errors, call fs::metadata and handle its Result. Then call fs::Metadata::is_dir if it was Ok.

Converts a Box<Path> into a PathBuf without copying or allocating.

Examples
use async_std::path::Path;

let path: Box<Path> = Path::new("foo.txt").into();
let path_buf = path.into_path_buf();

Trait Implementations

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Converts this type into a shared reference of the (usually inferred) input type.

Immutably borrows from an owned value. Read more

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Converts to this type from the input type.

Converts a Path into a Rc by copying the Path data into a new Rc buffer.

Converts to this type from the input type.

Converts to this type from the input type.

Converts to this type from the input type.

Converts to this type from the input type.

Feeds this value into the given Hasher. Read more

Feeds a slice of this type into the given Hasher. Read more

Converts this type into the (usually inferred) input type.

The type of the elements being iterated over.

Which kind of iterator are we turning this into?

Creates an iterator from a value. Read more

This method returns an Ordering between self and other. Read more

Compares and returns the maximum of two values. Read more

Compares and returns the minimum of two values. Read more

Restrict a value to a certain interval. Read more

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

This method returns an ordering between self and other values if one exists. Read more

This method tests less than (for self and other) and is used by the < operator. Read more

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

This method tests greater than (for self and other) and is used by the > operator. Read more

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

Uses borrowed data to replace owned data, usually by cloning. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more