filt

node filt

filt is for simple filters:

node -e 'require("filt")(line => line.toUpperCase())'

This module allows you to quickly write command-line filters - programs that read standard input line by line and print something on standard output.

Known problems

It prints an extra newline at the end - the split module used internally is apparently running the callback with an extra empty line at the end when there is none - I need to fix it.

Installation

Install to use in your project, updating the dependencies in package.json:

npm install filt --save

It currently has one dependency: split ...

Usage

Require the module:

var filt = require('filt');

Now filt is a function that gets a function that is called for each line of stdin.

Most basic usage:

filt(function (line) {
    console.log(line.toUpperCase());
});

Instead of calling console.log() you can also return a line to print:

filt(function (line) {
    return line.toUpperCase();
});

The same using ES6 syntax:

filt(line => line.toUpperCase());

Using require in the same line - this is the entire program:

require('filt')(line => line.toUpperCase());

Or straight from the command line:

node -e 'require("filt")(line => line.toUpperCase());'

Issues

For any bug reports or feature requests please post an issue on GitHub.

Author

Rafał Pocztarski - https://github.com/rsp

License

MIT License (Expat). See LICENSE.md for details.