You are reading the newest entry

Customizing a Trilium Report
Tuesday, 9 August, 2022

Emoji Breakdowns With Raku

In which I write a Raku emoji reverse lookup tool.
If you think that's weird, you should see what all these emoji have done to my neovim session.
Posted
post #raku lang
Got a comment? A question? More of a comment than a question? Talk to me about this page on: mastodon twitter

Had to share, but gotta make this quick because I am about three tangents removed from the stuff I planned to do today. This Raku script prints out code points for emoji characters with a little help from Pretty::Table.

#!/usr/bin/env raku

use Pretty::Table;

sub emoji-table(Str $emoji) {
  my $table = Pretty::Table.new:
    title => "Emoji Breakdown",
    field-names => [
      "Name",
      "Code",
      "Hex Code",
      "Emoji",
    ],
    border => False,
    align => %(
      Code => "r",
      "Hex Code" => "r",
    )
  ;

  for $emoji.ords -> $ord {
    my $chr = $ord.chr;
    $table.add-row: [
      $chr.uniname,
      $ord,
      $ord.base(16),
      $chr,
    ];
  }

  return $table;
}

sub MAIN(Str $emoji) {
  say "";
  say emoji-table($emoji);
}

And here’s what it looks like in action:

bsh ❯ rakumoji πŸ¦‹

| Emoji Breakdown |
    Name      Code  Hex Code  Emoji
 BUTTERFLY  129419     1F98B    πŸ¦‹

Why?

So I’m doing a thing with a CSS stylesheet involving display of emojis. You don’t want the emoji in a stylesheet though. More portable to use code points, the numeric value or values a computer uses to identify the character.

The problem: I don’t know the code point. I use a convenient emoji picker. All it gives me is a character.

I’ve had some luck looking this stuff up online. But why spend 10 seconds looking it up when I could spend half an hour writing code and another hour rationalizing my decision in a blog post?

Str.ord gets me the ordinal for a single character. That’s not always what I need though. What looks like a single character could be composed of several codepoints.

Unicode is weird.

Str.ords gives me a list of all code points in the string, whether one or several. I get the name of the emoji as well with str.uniname. I can use that name with Str.uniparse to get the emoji again.

bsh ❯ raku -e 'say "butterfly".uniparse;'
πŸ¦‹

Pretty::Table makes it look nice β€” or as nice as my terminal can manage β€” no matter how many code points are in the emoji.

bsh ❯ rakumoji πŸ„β€β™€οΈ

| Emoji Breakdown |
          Name            Code  Hex Code  Emoji
         SURFER         127940     1F3C4    πŸ„
   ZERO WIDTH JOINER      8205      200D    ‍
      FEMALE SIGN         9792      2640    ♀
 VARIATION SELECTOR-16   65039      FE0F    ️

I helped the terminal out by putting the emoji character at the end of each line. Otherwise the pretty table layouts get offset weird.

Anyways I had fun. And now I’m only two tangents away from the day’s intended tasks.