Which would you choose / use? :one: `it.toString(...

# codingconventions

[Chris]

Which would you choose / use?

1️⃣ it.toString()
or
2️⃣ "$it"
or
3️⃣ something else?

Is 1️⃣ and 2️⃣ equivalent?

[Michael Böiers]

I hadn’t thought about that before, but what’s so bad about 2? If it’s really equivalent (no performance penalty), it’s actually more concise.

[Michael Böiers]

The alternatives are also not equivalent when it comes to nullability … so 1 should be it?.toString() ?: "null"?

EDIT: I was wrong, they are equivalent. 🙂

[mkrussel]

The intention with 1 is more obvious.

And toString in Kotlin is an extension on Any? and handles null correctly.

[Chris]

I’ve only started thinking about it because i changed an instance of 1️⃣ to be an instance of 2️⃣ in my project and it introduced a IllegalFormatConversionException .

I’m still none the wiser as to why because they both produce a String.

[Michael Böiers]

@mkrussel nice! Didn’t know that it returns "null", would have expected null. I learn something new about Kotlin every day! 🙂

[Michael Böiers]

@Chris That exception usually occurs when you use something like String.format().

[Chris]

Yes, that’s exactly what i was doing. In an android project formatting a string for presenting on the screen. I find it very confusing as to how it was even a problem.