Pretty Log

Pretty log messages with color, format, and cursor manipulation.

npm install t-ski/pretty-log

Example Log

Example Source

prettyLog.BOLD.fg.WHITE.bg.color(128, 128, 255)(
  ` ${prettyLog.UNDERLINE("Example")} `
)

Synopsis

Pretty Log has a simple API: Provide an arbitrary chain of style expressions that are finally applied to a target string.

import prettyLog from "t-ski/pretty-log";

prettyLog.[<style-expression>]+(targetString: string): string;

Pretty log styled strings are nestable, i.e. can be embedded within styled strings themselves.

Style Expressions

Color

prettyLog.<fg|bg>.<Color>
// OR
prettyLog.<fg|bg>.color(r: number, g: number, b: number)
prettyLog.<fg|bg>.color(hex: string)

Color styles must be prepended by a color channel. fg indicates the foreground color channel, whereas bg is for the complementary background color channel.

| <Color> | RGB | | :- | -: | | BLACK | 0, 0, 0 | | GRAY | 128, 128, 128 | | WHITE | 255, 255, 255 | | RED | 255, 0, 0 | | ORANGE | 255, 128, 0 | | YELLOW | 255, 255, 0 | | LIME | 0, 255, 0 | | GREEN | 0, 255, 128 | | CYAN | 0, 255, 255 | | BLUE | 0, 0, 255 | | PURPLE | 128, 0, 255 | | PINK | 255, 0, 255 |

Example

prettyLog.bg.RED.fg.color(245, 245, 245)("Example");

Format

prettyLog.<Format>

| <Format> | Description | | :- | :- | | BOLD | Bold, i.e. higher intensity | | FAINT | Faint, i.e. lower intensity | | ITALIC | Italic | | UNDERLINE | Underlined | | DOUBLY_UNDERLINE | Doubly underlined | | BLINK | Blink effect | | INVERT | Invert coloring (fg ⇄ bg) | | STRIKE | Strike through, i.e. crossed out |

Whether and how styles are displayed depends on the console application.

Example

prettyLog.BOLD.UNDERLINE("Example");

Cursor

prettyLog.<Cursor>
// OR
prettyLog.cursor(x: number, y: number)

| <Cursor> | Description | | :- | :- | | UP | Up one line (row) (same as .cursor(0, 1)) | | DOWN | Down one line (same as .cursor(0, -1)) | | LEFT | Left one space (column) (same as .cursor(-1, 0)) | | RIGHT | Right one space (same as .cursor(1, 0)) | | CLEAR | Clear current line | | ERASE | Clear the last completed line (\n) | | STORE | Store the current cursor position | | RESTORE | Restore the current cursor position |

Example

prettyLog.CLEAR(".".repeat((++iteration % 3) + 1));

Macros

Assigning frequently used style chains to reusable macro variables might be helpful:

const CODE = prettyLog.BOLD.fg.ORANGE;
console.log(CODE(".method()"));

function badge(message) {
  console.log(
    prettyLog.BOLD.fg.WHITE.bg.color(128, 128, 255)(
      ` ${prettyLog.UNDERLINE(message.toUpperCase())} `
    )
  );
}
badge("Results");

© Thassilo Martin Schiepanski