function emitKeypressEvents
Usage in Deno
```typescript import { emitKeypressEvents } from "node:node__readline.d.ts"; ```
emitKeypressEvents(stream: ReadableStream,readlineInterface?: Interface,): void
The `readline.emitKeypressEvents()` method causes the given `Readable` stream to begin emitting `'keypress'` events corresponding to received input.
Optionally, `interface` specifies a `readline.Interface` instance for which
autocompletion is disabled when copy-pasted input is detected.
If the `stream` is a `TTY`, then it must be in raw mode.
This is automatically called by any readline instance on its `input` if the `input` is a terminal. Closing the `readline` instance does not stop
the `input` from emitting `'keypress'` events.
```js
readline.emitKeypressEvents(process.stdin);
if (process.stdin.isTTY)
process.stdin.setRawMode(true);
```
## Example: Tiny CLI
The following example illustrates the use of `readline.Interface` class to
implement a small command-line interface:
```js
import readline from 'node:readline';
const rl = readline.createInterface({
input: process.stdin,
output: process.stdout,
prompt: 'OHAI> ',
});
rl.prompt();
rl.on('line', (line) => {
switch (line.trim()) {
case 'hello':
console.log('world!');
break;
default:
console.log(`Say what? I might have heard '${line.trim()}'`);
break;
}
rl.prompt();
}).on('close', () => {
console.log('Have a great day!');
process.exit(0);
});
```
## Example: Read file stream line-by-Line
A common use case for `readline` is to consume an input file one line at a
time. The easiest way to do so is leveraging the `fs.ReadStream` API as
well as a `for await...of` loop:
```js
import fs from 'node:fs';
import readline from 'node:readline';
async function processLineByLine() {
const fileStream = fs.createReadStream('input.txt');
const rl = readline.createInterface({
input: fileStream,
crlfDelay: Infinity,
});
// Note: we use the crlfDelay option to recognize all instances of CR LF
// ('\r\n') in input.txt as a single line break.
for await (const line of rl) {
// Each line in input.txt will be successively available here as `line`.
console.log(`Line from file: ${line}`);
}
}
processLineByLine();
```
Alternatively, one could use the `'line'` event:
```js
import fs from 'node:fs';
import readline from 'node:readline';
const rl = readline.createInterface({
input: fs.createReadStream('sample.txt'),
crlfDelay: Infinity,
});
rl.on('line', (line) => {
console.log(`Line from file: ${line}`);
});
```
Currently, `for await...of` loop can be a bit slower. If `async` / `await` flow and speed are both essential, a mixed approach can be applied:
```js
import { once } from 'node:events';
import { createReadStream } from 'node:fs';
import { createInterface } from 'node:readline';
(async function processLineByLine() {
try {
const rl = createInterface({
input: createReadStream('big-file.txt'),
crlfDelay: Infinity,
});
rl.on('line', (line) => {
// Process the line.
});
await once(rl, 'close');
console.log('File processed.');
} catch (err) {
console.error(err);
}
})();
```
optional
readlineInterface: Interface
void