Struct clio::Input

pub struct Input { /* private fields */ }

An enum that represents a command line input stream, either Stdin or File

It is designed to be used with the clap crate when taking a file name as an argument to CLI app

use clap::Parser;
use clio::Input;

#[derive(Parser)]
struct Opt {
    /// path to file, use '-' for stdin
    #[clap(value_parser)]
    input_file: Input,
}

Implementations

impl Input

pub fn new<S: TryInto<ClioPath>>(path: S) -> Result<Self>where Error: From<<S as TryInto<ClioPath>>::Error>,

Contructs a new input either by opening the file or for ‘-’ returning stdin

pub fn std() -> Self

Contructs a new input for stdin

pub fn try_from_os_str(path: &OsStr) -> Result<Self, OsString>

Contructs a new input either by opening the file or for ‘-’ returning stdin

The error is converted to a OsString so that stuctopt can show it to the user.

It is recomended that you use TryFrom::try_from and clap 3.0 instead.

pub fn len(&self) -> Option<u64>

If input is a file, returns the size of the file, in bytes otherwise if input is stdin returns none.

Examples

let file = clio::Input::new("foo.txt").unwrap();

assert_eq!(Some(3), file.len());

pub fn get_file(&mut self) -> Option<&mut File>

If input is a file, returns a reference to the file, otherwise if input is stdin or a pipe returns none.

pub fn is_empty(&self) -> Option<bool>

Returns a boolean saying if the file is empty, if using stdin returns None

Examples

let file = clio::Input::new("foo.txt").unwrap();

assert_eq!(Some(true), file.is_empty());

pub fn lock<'a>(&'a mut self) -> Box<dyn BufRead + 'a>

If the input is std in locks it, otherwise wraps the file in a buffered reader. This is useful to get the line iterator of the BufRead.

Examples

use std::io::BufRead;
let mut file = clio::Input::new("-")?;

for line in file.lock().lines() {
  println!("line is: {}", line?);
}

pub fn path(&self) -> &ClioPath

Returns the path/url used to create the input

pub fn can_seek(&self) -> bool

Returns true if this Input is a file, and false if this Input is std out or a pipe

Trait Implementations

impl Clone for Input

Available on crate feature clap-parse only.

Opens a new handle on the file from the path that was used to create it Probbably a bad idea to have two write handles to the same file or to std in There is no effort done to make the clone be at the same position as the original

This will panic if the file has been deleted

Only included when using the clap-parse fature as it is needed for value_parser

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Input

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Input

fn default() -> Self

Returns the “default value” for a type.

impl Display for Input

formats as the path it was created from

fn fmt(&self, fmt: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Read for Input

fn read(&mut self, buf: &mut [u8]) -> IoResult<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

fn is_read_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation.

fn read_to_end(&mut self, buf: &mut Vec<u8, Global>) -> Result<usize, Error>

Read all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Read all bytes until EOF in this source, appending them to buf.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Read the exact number of bytes required to fill buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Pull some bytes from this source into the specified buffer.

fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Read the exact number of bytes required to fill cursor.

fn by_ref(&mut self) -> &mut Selfwhere Self: Sized,

Creates a “by reference” adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R>where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>where Self: Sized,

Creates an adapter which will read at most limit bytes from it.

impl Seek for Input

fn seek(&mut self, pos: SeekFrom) -> IoResult<u64>

Seek to an offset, in bytes, in a stream.

fn rewind(&mut self) -> Result<(), Error>

Rewind to the beginning of a stream.

fn stream_len(&mut self) -> Result<u64, Error>

🔬This is a nightly-only experimental API. (seek_stream_len)

Returns the length of this stream (in bytes).

fn stream_position(&mut self) -> Result<u64, Error>

Returns the current seek position from the start of the stream.

impl TryFrom<&OsStr> for Input

type Error = Error

The type returned in the event of a conversion error.

fn try_from(file_name: &OsStr) -> Result<Self>

Performs the conversion.

impl TryFrom<&OsString> for Input

type Error = Error

The type returned in the event of a conversion error.

fn try_from(file_name: &OsString) -> Result<Self>

Performs the conversion.

impl TryFrom<&Path> for Input

type Error = Error

The type returned in the event of a conversion error.

fn try_from(file_name: &Path) -> Result<Self>

Performs the conversion.

impl TryFrom<&PathBuf> for Input

type Error = Error

The type returned in the event of a conversion error.

fn try_from(file_name: &PathBuf) -> Result<Self>

Performs the conversion.

impl TryFrom<&String> for Input

type Error = Error

The type returned in the event of a conversion error.

fn try_from(file_name: &String) -> Result<Self>

Performs the conversion.

impl TryFrom<&str> for Input

type Error = Error

The type returned in the event of a conversion error.

fn try_from(file_name: &str) -> Result<Self>

Performs the conversion.

impl TryFrom<ClioPath> for Input

type Error = Error

The type returned in the event of a conversion error.

fn try_from(file_name: ClioPath) -> Result<Self>

Performs the conversion.

impl ValueParserFactory for Input

Available on crate feature clap-parse only.

type Parser = OsStrParser<Input>

Generated parser, usually ValueParser.

fn value_parser() -> Self::Parser

Create the specified Self::Parser