Stylog NPM | npm.io

Introduction

Stylog is a stylish way how to easily format rich console.log messages.

It's overengineered on purpose I just wanted to write it in the "old school" way and avoid RegExps. It has been written with a nostalgic memory to the Dragon Book 🐲

Install

yarn add stylog

The library is targeted for the last two version of Chrome, it's designed to be used mostly in dev mode within latest dev tools.

Usage

API

stylog(
  (recipe: string),
  (stylesDictionary: ?{
    [id: string]: {
      [property: string]: string
    }
  }),
  (mapperDictionary ?{
    [id: string]: (value: string) => string
  })
);

If you are fan of FP you can take full advantage of the data-last curried version!✌️

stylog.fp(mapperDictionary)(stylesDictionary)(recipe);

Recipe

text is everything outside (non-escaped) "{"
styled text start with "{" followed by id (string) and optionally text (multiline string) then it should be closed with "}"
each styled text may have corresponding style in stylesDictionary otherwise it would be rendered as text
styled text can be escaped by \ (in template literal you have to use \\ ) then it would be considered as text

This is normal text {styled this is styled text}

This is normal text \{styled this is also normal text}

Styles Dictionary

is an nullable-object where key should be string matching id of styled text and value is supposed to be object of CSS properties in camelCase notation.
it could be null

{
  styled: {
    fontSize: "20px"; // or "fontSize: 20" :)
  }
}

Mapper Dictionary

is an nullable-object where key should be string matching id of styled text and value is supposed to be an function which takes that matched string and returns modified string (optionally could return falsy value which will act as empty string)

{
  // return c👏l👏a👏p👏e👏d string
  clap: s => {
    return [...s]
      .map((a, i) => `${a}${i !== s.length - 1 ? "👏" : ""}`)
      .join("");
  };
}

Example

Check it out the example/index.html for interactive playground! 🙌

stylog(
  `{big Hello, everyone! This is nicely styled text!} 
and non-styled text. Lovely, right? {bold *clap* *clap* *clap*} 

{image [GANDALF]} {red Be aware! Wild Gandalf appears!}

.
.
.

\\{gandalf}

.
.
.

not like this

.
.
.
{gandalf}

{clap Awesome}`,
  {
    bold: {
      fontWeight: "bold"
    },
    big: {
      fontSize: "25px",
      border: "1px solid black",
      padding: "10px"
    },
    image: {
      display: "block !important",
      color: "gray",
      fontSize: "10px",
      background: `url("https://vignette.wikia.nocookie.net/casshan/images/d/dc/Warn.png/revision/latest?cb=20120614181856")`,
      backgroundSize: "15px 15px",
      backgroundRepeat: "no-repeat",
      backgroundPosition: "left",
      paddingLeft: "15px"
    },
    red: {
      color: "red",
      textDecoration: "underline"
    },
    gandalf: {
      display: "block !important",
      color: "gray",
      fontSize: "300px",
      lineHeight: "150px",
      display: "block !important",
      background: `url("https://i.giphy.com/media/FyetIxXamPsfC/giphy.webp")`,
      backgroundSize: "200px",
      backgroundRepeat: "no-repeat",
      backgroundPosition: "left"
    },
    clap: {
      background: "black",
      color: "yellow"
    }
  },
  {
    clap: s => {
      return [...s]
        .map((a, i) => `${a}${i !== s.length - 1 ? "👏" : ""}`)
        .join("");
    }
  }
);

will produce this:

Contributing

Do you miss something? Open an issue, I'd like to hear more about your use case. You can also fork this repository and run yarn && yarn dev, do stuff in the playground (example/index.html), then run yarn test and finally send a PR! ❤️