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§
source§impl Path
impl Path
sourcepub fn new<S: AsRef<OsStr> + ?Sized>(s: &S) -> &Path
pub fn new<S: AsRef<OsStr> + ?Sized>(s: &S) -> &Path
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);sourcepub fn to_str(&self) -> Option<&str>
pub fn to_str(&self) -> Option<&str>
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"));sourcepub fn to_string_lossy(&self) -> Cow<'_, str>
pub fn to_string_lossy(&self) -> Cow<'_, str>
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".
sourcepub fn to_path_buf(&self) -> PathBuf
pub fn to_path_buf(&self) -> PathBuf
sourcepub fn is_absolute(&self) -> bool
pub fn is_absolute(&self) -> bool
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_absoluteandhas_rootare equivalent. -
On Windows, a path is absolute if it has a prefix and starts with the root:
c:\windowsis absolute, whilec:tempand\tempare not.
§Examples
use async_std::path::Path;
assert!(!Path::new("foo.txt").is_absolute());sourcepub fn is_relative(&self) -> bool
pub fn is_relative(&self) -> bool
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());sourcepub fn has_root(&self) -> bool
pub fn has_root(&self) -> bool
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:\windowsbut notc:windows - has any non-disk prefix, e.g.
\\server\share
- has no prefix and begins with a separator, e.g.
§Examples
use async_std::path::Path;
assert!(Path::new("/etc/passwd").has_root());sourcepub fn parent(&self) -> Option<&Path>
pub fn parent(&self) -> Option<&Path>
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);sourcepub fn ancestors(&self) -> Ancestors<'_> ⓘ
pub fn ancestors(&self) -> Ancestors<'_> ⓘ
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);sourcepub fn file_name(&self) -> Option<&OsStr>
pub fn file_name(&self) -> Option<&OsStr>
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());sourcepub fn strip_prefix<P>(&self, base: P) -> Result<&Path, StripPrefixError>
pub fn strip_prefix<P>(&self, base: P) -> Result<&Path, StripPrefixError>
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")));sourcepub fn starts_with<P: AsRef<Path>>(&self, base: P) -> bool
pub fn starts_with<P: AsRef<Path>>(&self, base: P) -> bool
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"));sourcepub fn ends_with<P: AsRef<Path>>(&self, child: P) -> bool
pub fn ends_with<P: AsRef<Path>>(&self, child: P) -> bool
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"));sourcepub fn file_stem(&self) -> Option<&OsStr>
pub fn file_stem(&self) -> Option<&OsStr>
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());sourcepub fn extension(&self) -> Option<&OsStr>
pub fn extension(&self) -> Option<&OsStr>
Extracts the extension of file_name, if possible.
The extension is:
None, if there is no file nameNone, 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());sourcepub fn join<P: AsRef<Path>>(&self, path: P) -> PathBuf
pub fn join<P: AsRef<Path>>(&self, path: P) -> PathBuf
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"));sourcepub fn with_file_name<S: AsRef<OsStr>>(&self, file_name: S) -> PathBuf
pub fn with_file_name<S: AsRef<OsStr>>(&self, file_name: S) -> PathBuf
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"));sourcepub fn with_extension<S: AsRef<OsStr>>(&self, extension: S) -> PathBuf
pub fn with_extension<S: AsRef<OsStr>>(&self, extension: S) -> PathBuf
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"));sourcepub fn components(&self) -> Components<'_> ⓘ
pub fn components(&self) -> Components<'_> ⓘ
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/banda//bboth haveaandbas components. -
Occurrences of
.are normalized away, except if they are at the beginning of the path. For example,a/./b,a/b/,a/b/.anda/ball haveaandbas components, but./a/bstarts with an additionalCurDircomponent. -
A trailing slash is normalized away,
/a/band/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);sourcepub fn iter(&self) -> Iter<'_> ⓘ
pub fn iter(&self) -> Iter<'_> ⓘ
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)sourcepub async fn metadata(&self) -> Result<Metadata>
pub async fn metadata(&self) -> Result<Metadata>
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());sourcepub async fn symlink_metadata(&self) -> Result<Metadata>
pub async fn symlink_metadata(&self) -> Result<Metadata>
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());sourcepub async fn canonicalize(&self) -> Result<PathBuf>
pub async fn canonicalize(&self) -> Result<PathBuf>
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"));sourcepub async fn read_link(&self) -> Result<PathBuf>
pub async fn read_link(&self) -> Result<PathBuf>
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?;sourcepub async fn read_dir(&self) -> Result<ReadDir>
pub async fn read_dir(&self) -> Result<ReadDir>
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());
}sourcepub async fn exists(&self) -> bool
pub async fn exists(&self) -> bool
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.
sourcepub async fn is_file(&self) -> bool
pub async fn is_file(&self) -> bool
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.
sourcepub async fn is_dir(&self) -> bool
pub async fn is_dir(&self) -> bool
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.