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I/O - Deno documentation

Enums

E
Deno.SeekMode
A enum which defines the seek mode for IO related APIs that support seeking.

Functions

f
Deno.consoleSize
Gets the size of the console as columns/rows. ```ts const { columns, rows } = Deno.consoleSize(); ``` This returns the size of the console window as reported by the operating system. It's not a reflection of how many characters will fit within the console window, but can be used as part of that calculation.
f
Deno.inspect
Converts the input into a string that has the same format as printed by `console.log()`. ```ts const obj = { a: 10, b: "hello", }; const objAsString = Deno.inspect(obj); // { a: 10, b: "hello" } console.log(obj); // prints same value as objAsString, e.g. { a: 10, b: "hello" } ``` A custom inspect functions can be registered on objects, via the symbol `Symbol.for("Deno.customInspect")`, to control and customize the output of `inspect()` or when using `console` logging: ```ts class A { x = 10; y = "hello"; [Symbol.for("Deno.customInspect")]() { return `x=${this.x}, y=${this.y}`; } } const inStringFormat = Deno.inspect(new A()); // "x=10, y=hello" console.log(inStringFormat); // prints "x=10, y=hello" ``` A depth can be specified by using the `depth` option: ```ts Deno.inspect({a: {b: {c: {d: 'hello'}}}}, {depth: 2}); // { a: { b: [Object] } } ```

Interfaces

I
Deno.SetRawOptions
No documentation available

Variables

v
Deno.stderr
A reference to `stderr` which can be used to write directly to `stderr`. It implements the Deno specific [`Writer`](https://jsr.io/@std/io/doc/types/~/Writer), [`WriterSync`](https://jsr.io/@std/io/doc/types/~/WriterSync), and [`Closer`](https://jsr.io/@std/io/doc/types/~/Closer) interfaces as well as provides a `WritableStream` interface. These are low level constructs, and the `console` interface is a more straight forward way to interact with `stdout` and `stderr`.
v
Deno.stdin
A reference to `stdin` which can be used to read directly from `stdin`. It implements the Deno specific [`Reader`](https://jsr.io/@std/io/doc/types/~/Reader), [`ReaderSync`](https://jsr.io/@std/io/doc/types/~/ReaderSync), and [`Closer`](https://jsr.io/@std/io/doc/types/~/Closer) interfaces as well as provides a `ReadableStream` interface. ### Reading chunks from the readable stream ```ts const decoder = new TextDecoder(); for await (const chunk of Deno.stdin.readable) { const text = decoder.decode(chunk); // do something with the text } ```
v
Deno.stdout
A reference to `stdout` which can be used to write directly to `stdout`. It implements the Deno specific [`Writer`](https://jsr.io/@std/io/doc/types/~/Writer), [`WriterSync`](https://jsr.io/@std/io/doc/types/~/WriterSync), and [`Closer`](https://jsr.io/@std/io/doc/types/~/Closer) interfaces as well as provides a `WritableStream` interface. These are low level constructs, and the `console` interface is a more straight forward way to interact with `stdout` and `stderr`.