Struct IndentWriter

pub struct IndentWriter<'i, W> { /* private fields */ }

Adapter for writers to indent each line

An IndentWriter adapts an io::Write object to insert an indent before each non-empty line. Specifically, this means it will insert an indent between each newline when followed by a non-newline.

These writers can be nested to provide increasing levels of indentation.

Example

use indent_write::io::IndentWriter;

let output = Vec::new();

let mut indented = IndentWriter::new("\t", output);

// Lines will be indented
write!(indented, "Line 1\nLine 2\n");

// Empty lines will not be indented
write!(indented, "\n\nLine 3\n\n");

assert_eq!(indented.get_ref(), b"\tLine 1\n\tLine 2\n\n\n\tLine 3\n\n");

Implementations

impl<'i, W: Write> IndentWriter<'i, W>

pub fn new(indent: &'i str, writer: W) -> Self

Create a new IndentWriter.

pub fn new_skip_initial(indent: &'i str, writer: W) -> Self

Create a new IndentWriter which will not add an indent to the first written line.

Example

use indent_write::io::IndentWriter;

let mut buffer = Vec::new();
let mut writer = IndentWriter::new_skip_initial("    ", &mut buffer);

writeln!(writer, "Line 1").unwrap();
writeln!(writer, "Line 2").unwrap();
writeln!(writer, "Line 3").unwrap();

assert_eq!(buffer, b"Line 1\n    Line 2\n    Line 3\n")

pub fn into_inner(self) -> W

Extract the writer from the IndentWriter, discarding any in-progress indent state.

pub fn get_ref(&self) -> &W

Get a reference to the wrapped writer

pub fn indent(&self) -> &'i str

Get the string being used as an indent for each line

Trait Implementations

impl<'i, W: Clone> Clone for IndentWriter<'i, W>

fn clone(&self) -> IndentWriter<'i, W>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'i, W: Debug> Debug for IndentWriter<'i, W>

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

Formats the value using the given formatter.

impl<'i, W: Write> Write for IndentWriter<'i, W>

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

Writes a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination.

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

Like write, except that it writes from a slice of buffers.

fn is_write_vectored(&self) -> bool

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

Determines if this Writer has an efficient write_vectored implementation.

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

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

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

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, fmt: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.