Skip to main content
Module

std/types.d.ts

Deno standard library
Go to Latest
File
// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
/** See the Contributing > Types section in the README for an explanation of this file. */
/** An abstract interface which when implemented provides an interface to read bytes into an array buffer asynchronously. */export interface Reader { /** Reads up to `p.byteLength` bytes into `p`. It resolves to the number of * bytes read (`0` < `n` <= `p.byteLength`) and rejects if any error * encountered. Even if `read()` resolves to `n` < `p.byteLength`, it may * use all of `p` as scratch space during the call. If some data is * available but not `p.byteLength` bytes, `read()` conventionally resolves * to what is available instead of waiting for more. * * When `read()` encounters end-of-file condition, it resolves to EOF * (`null`). * * When `read()` encounters an error, it rejects with an error. * * Callers should always process the `n` > `0` bytes returned before * considering the EOF (`null`). Doing so correctly handles I/O errors that * happen after reading some bytes and also both of the allowed EOF * behaviors. * * Implementations should not retain a reference to `p`. * * Use iterateReader() from https://deno.land/std@$STD_VERSION/streams/iterate_reader.ts to turn a Reader into an * AsyncIterator. */ read(p: Uint8Array): Promise<number | null>;}
/** An abstract interface which when implemented provides an interface to read bytes into an array buffer synchronously. */export interface ReaderSync { /** Reads up to `p.byteLength` bytes into `p`. It resolves to the number * of bytes read (`0` < `n` <= `p.byteLength`) and rejects if any error * encountered. Even if `read()` returns `n` < `p.byteLength`, it may use * all of `p` as scratch space during the call. If some data is available * but not `p.byteLength` bytes, `read()` conventionally returns what is * available instead of waiting for more. * * When `readSync()` encounters end-of-file condition, it returns EOF * (`null`). * * When `readSync()` encounters an error, it throws with an error. * * Callers should always process the `n` > `0` bytes returned before * considering the EOF (`null`). Doing so correctly handles I/O errors that happen * after reading some bytes and also both of the allowed EOF behaviors. * * Implementations should not retain a reference to `p`. * * Use iterateReaderSync() from https://deno.land/std@$STD_VERSION/streams/iterate_reader.ts to turn a ReaderSync * into an Iterator. */ readSync(p: Uint8Array): number | null;}
/** An abstract interface which when implemented provides an interface to write bytes from an array buffer to a file/resource asynchronously. */export interface Writer { /** Writes `p.byteLength` bytes from `p` to the underlying data stream. It * resolves to the number of bytes written from `p` (`0` <= `n` <= * `p.byteLength`) or reject with the error encountered that caused the * write to stop early. `write()` must reject with a non-null error if * would resolve to `n` < `p.byteLength`. `write()` must not modify the * slice data, even temporarily. * * Implementations should not retain a reference to `p`. */ write(p: Uint8Array): Promise<number>;}/** An abstract interface which when implemented provides an interface to write bytes from an array buffer to a file/resource synchronously. */export interface WriterSync { /** Writes `p.byteLength` bytes from `p` to the underlying data * stream. It returns the number of bytes written from `p` (`0` <= `n` * <= `p.byteLength`) and any error encountered that caused the write to * stop early. `writeSync()` must throw a non-null error if it returns `n` < * `p.byteLength`. `writeSync()` must not modify the slice data, even * temporarily. * * Implementations should not retain a reference to `p`. */ writeSync(p: Uint8Array): number;}
/** An abstract interface which when implemented provides an interface to close files/resources that were previously opened. */export interface Closer { /** Closes the resource, "freeing" the backing file/resource. */ close(): void;}