Interval Template Strings

A simple package that allows you to use nicely formatted interval strings when working with time.

This package was made with inspiration from the sql-template-strings package.

Working with intervals in nodejs can be kind of sloppy from time to time. Constantly having to go over how much milliseconds a specific time actually is, constantly having to recalculate back and forth on it, and in worst case cenario, make your timings hard to read. This package brings a fix to that problem with only a single import and no additional dependencies.

How?

Thanks to javascript's beautiful processing of template strings, it's as easy as;

import { T } from 'interval-template-strings';
// long
T`3 hours 20 seconds`
// or short
T`3h20s`
// using HH:MM format
T`03:04`
// or HH:MM:SS
T`03:04:05`
// positive or negative
T`3d - 1d + 12:40:05` // will be the same as T`3d - 1d 12h 40m 5s`
// and a convertible output:
T`3d -12:40:05;d` // This will be in seconds!

Unit definitions

The package allows units to be written in singular, plural and in short form. Their values can be written as integer, floating point and even negative values.

Unit	Short form
milliseconds	ms
seconds	s
minutes	m
hours	h
days	d
months	mo
years	y

New Time format

From a feature request, instead of writing 1w 2d 3h 4m 5s you can now write 1w 2d 03:04:05 or without seconds, 1w 2d 03:04

New Flags

Due to my own constant irritation to converting back and forth to Date to get offsets for now or database formats (previously _T), a flag system has been added to convert your output to your desired numeric format. Neat!

Flag	Description
n	Value adjusted to offset Date.now()
d	Value adjusted to seconds for SQL formats

Some examples

/*
* Adding an element to an array every 2.5 hours
*/
let myArray = [];
let i = 0;
setInterval(() => {
	myArray.push(i++);
}, 1000 * 60 * 60 * 2.5);

With template string:

import { T } from 'interval-template-strings';
let myArray = [];
let i = 0;
setInterval(() => {
myArray.push(i++);
}, T`2.5 hours`);

Or the long way;

const SECOND = 1000;
const MINUTE = SECOND * 60;
const HOUR = MINUTE * 60;
const DAY = HOUR * 24;
console.log("I'll see you in 3 days!");
setTimeout(() =>  console.log("I last saw you 3 days ago!"), DAY * 3);

With template string;

import { T } from 'interval-template-strings';
console.log("I'll see you in 3 days!");
setTimeout(() =>  console.log("I last saw you 3 days ago!"), T`3 days`);

Or if you don't like to use T;

import { T as INTERVAL } from 'interval-template-strings';
console.log(INTERVAL`30 seconds`);

Contributing

• Tests are written with Mocha
• Currently there's no linter configured but I might change this in the future.
• I am open for pull requests, feature enhancements and bug reports.

Start up the environment by pulling the git and running npm install. Run tests with npm test.

Version history

1.0

• Added T and _T for converting strings and one to convert to database formats
• Setup tests

1.1

• Removed _T
• Typescriptified the whole project
• Added HH:MM:SS and HH:MM support
• Added flags n for offsetting to Date.now(), d to replace _T and convert the output to seconds
• Grouped all functions to classes
• Added more typescript types

Special thanks

• FinlayDaG33k for initial typescript definitions