Working with Input

Send data to process stdin.

Choosing Your Approach

Use .run() for process-to-process pipes (most common):

await run("cat", "file.txt").run("grep", "pattern").toStdout();

Use enumerate() for in-memory data:

await enumerate(["line1", "line2"]).run("grep", "1").toStdout();

Use read() for file input:

await read("input.txt").run("grep", "pattern").toStdout();

Use range() for generated sequences:

await range({ to: 100 }).map(n => n.toString()).run("shuf").toStdout();

Piping Between Processes

The most common way to provide input:

import { run } from "jsr:@j50n/proc@0.23.3";

await run("echo", "hello")
  .run("tr", "a-z", "A-Z")  // Receives "hello" as stdin
  .toStdout();
// HELLO

From Enumerable

Pipe any enumerable to a process:

import { enumerate } from "jsr:@j50n/proc@0.23.3";

const data = ["line 1", "line 2", "line 3"];

await enumerate(data)
  .run("grep", "2")
  .toStdout();
// line 2

From File

import { read } from "jsr:@j50n/proc@0.23.3";

await read("input.txt")
  .run("grep", "pattern")
  .toStdout();

Real-World Examples

Filter Data

await read("data.txt")
  .run("grep", "ERROR")
  .run("sort")
  .run("uniq")
  .toStdout();

Transform and Process

await read("input.txt")
  .lines
  .map(line => line.toUpperCase())
  .run("sort")
  .toStdout();

Generate and Process

import { range } from "jsr:@j50n/proc@0.23.3";

await range({ to: 100 })
  .map(n => n.toString())
  .run("shuf")  // Shuffle
  .run("head", "-10")
  .toStdout();

Next Steps

Process Pipelines - Chain commands
Working with Output - Capture results

Keyboard shortcuts

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