ldebug

ldebug

A debugging utility that evaluates messages lazily.

Usage

import { createDebug } from 'ldebug';
import process from 'node:process';

const debug = createDebug({
  isDevelopment: process.env.NODE_ENV !== 'production',
  highlight: true,
  prettyStringify: true,
});

// The following line will log "Hello ['world']" with colors in development and do nothing in production (the template string won't be evaluated either).
debug((f) => f`Hello ${['world']}`);

API

createDebug(options)

Returns: LazyDebugFunction

Creates a new debug function with the given options.

options.isDevelopment

Type: boolean
Required: true

A boolean representing whether or not the application is running in development. If the application is not running in the development, createDebug will return a no-op function.

options.highlight

Type: boolean
Default: true

Highlights the messages using cli-highlighter.

options.prettyStringify

Type: boolean
Default: true

If true, uses [json-stringify-pretty-compact] to stringify objects. Otherwise, uses JSON.stringify().

options.logger

Type: (message: string) => void
Default: console.log

A custom logger function to use when logging debug messages.

LazyDebugFunction

Type: (callback: (format: FormatHelper) => string) => void

callback

The callback (only called in development) that returns the message to log.

format

Type: FormatHelper

export type FormatHelper = (
  strings: TemplateStringsArray,
  ...values: unknown[]
) => string;

A format helper ES6 template tag that applies transformations to the strings and values in the template string (e.g. formatting and highlighting) for more readable output.