Custom console.log formatting for a class/object

[knotty shale]

Is there a way to change the way an object/class is printed in the console?

For example, instead of

[1, 2, 3, 4]
```, I want the particular object to be printed as

[1, 2
3, 4]

[dusky torrent]

see Deno.inspect https://deno.land/api@v1.35.1?s=Deno.inspect

you can specify some options for how you want the object to be displayed https://deno.land/api@v1.35.1?s=Deno.InspectOptions

if you want to have a more specific way of displaying your object, you can use the Deno.customInspect symbol to implement your own way of inspecting the object https://deno.land/manual@v1.35.1/basics/testing/snapshot_testing#serialization-with--denocustominspect

Here's a little example it showing off

const myarray = [1, 2, 3, 4, 5, 6];

console.log(myarray);
console.log(Deno.inspect(myarray, {
  breakLength: 28,
}));
Object.defineProperty(myarray, Symbol.for("Deno.customInspect"), {
  value() {
    const splits = String(this).split(",");
    let str = "";
    for (let i = 0; i < splits.length; i += 2) {
      str += (i !== 0 ? " " : "") + (splits[i] + ", " + splits[i + 1] ?? "") +
        (i > splits.length / 2 ? "" : "\n");
    }
    return `[${str}]`;
  },
});
console.log(myarray);

stdout

[ 1, 2, 3, 4, 5, 6 ]
[
  1,
  2,
  3,
  4,
  5,
  6
]
[1, 2
 3, 4
 5, 6]

you can also define it for specific object classes as well if you want, or implement the symbol in your own class

Object.defineProperty(Array.prototype, Symbol.for("Deno.customInspect"), { ... })

[knotty shale]

Ooh thank you