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Module

std/io/mod.ts

The Deno Standard Library
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The Standard Library has been moved to JSR. See the blog post for details.
import * as mod from "https://deno.land/std@0.222.1/io/mod.ts";

Utilities for working with Deno's readers, writers, and web streams.

Reader and Writer interfaces are deprecated in Deno, and so many of these utilities are also deprecated. Consider using web streams instead.

Classes

A variable-sized buffer of bytes with read() and write() methods.

c
BufferFullError
deprecated
c
BufReader
deprecated
c
BufWriter
deprecated

BufWriter implements buffering for an deno.Writer object. If an error occurs writing to a Writer, no more data will be accepted and all subsequent writes, and flush(), will return the error. After all data has been written, the client should call the flush() method to guarantee all data has been forwarded to the underlying deno.Writer.

c
BufWriterSync
deprecated

BufWriterSync implements buffering for a deno.WriterSync object. If an error occurs writing to a WriterSync, no more data will be accepted and all subsequent writes, and flush(), will return the error. After all data has been written, the client should call the flush() method to guarantee all data has been forwarded to the underlying deno.WriterSync.

c
LimitedReader
deprecated
c
MultiReader
deprecated

Reader utility for combining multiple readers

c
PartialReadError
deprecated
c
StringReader
deprecated

Reader utility for strings.

c
StringWriter
deprecated

Writer utility for buffering string chunks.

Functions

Copies from src to dst until either EOF (null) is read from src or an error occurs. It resolves to the number of bytes copied or rejects with the first error encountered while copying.

f
copyN
deprecated

Copy N size at the most. If read size is lesser than N, then returns nread

Turns a Reader into an async iterator.

Turns a ReaderSync into an iterator.

Read Reader r until EOF (null) and resolve to the content as Uint8Array.

Synchronously reads ReaderSync r until EOF (null) and returns the content as Uint8Array.

f
readDelim
deprecated

Read delimited bytes from a Reader.

f
readInt
deprecated

Read big endian 32bit integer from BufReader

f
readLines
deprecated

Read strings line-by-line from a Reader.

f
readLong
deprecated

Read big endian 64bit long from BufReader

f
readRange
deprecated

Read a range of bytes from a file or other resource that is readable and seekable. The range start and end are inclusive of the bytes within that range.

f
readRangeSync
deprecated

Read a range of bytes synchronously from a file or other resource that is readable and seekable. The range start and end are inclusive of the bytes within that range.

f
readShort
deprecated

Read big endian 16bit short from BufReader

f
readStringDelim
deprecated

Read Reader chunk by chunk, splitting based on delimiter.

f
sliceLongToBytes
deprecated

Slice number into 64bit big endian byte array

Create a ReadableStream of Uint8Arrays from a Reader.

Create a WritableStream from a Writer.

Write all the content of the array buffer (arr) to the writer (w).

Synchronously write all the content of the array buffer (arr) to the writer (w).

Interfaces

I
ByteRange
deprecated

An abstract interface which when implemented provides an interface to close files/resources that were previously opened.

An abstract interface which when implemented provides an interface to read bytes into an array buffer asynchronously.

An abstract interface which when implemented provides an interface to read bytes into an array buffer synchronously.

I
ReadLineResult
deprecated

Result type returned by of BufReader.readLine().

Options for toReadableStream.

Options for toWritableStream.

An abstract interface which when implemented provides an interface to write bytes from an array buffer to a file/resource asynchronously.

An abstract interface which when implemented provides an interface to write bytes from an array buffer to a file/resource synchronously.