yea i do get when you assign to a property, or when you need a expression, but other than that im no...

# getting-started

[ursus]

yea i do get when you assign to a property, or when you need a expression, but other than that im not sold on it, "?.let { }" why not just if != null

[Andreas Sinz]

it allows you to scope something to a specific code block

[ursus]

well any { } is a block with its own local vars

[ursus]

oh its not in kotlin, i see

[SiebelsTim]

When you have a variable that is shared across threads, if (x != null) x.doSmth() is not safe, as x could've changed to null in the meantime. let uses a temporary to guarantee that it is not affected by other threads.

[ursus]

yes ive been just shown that, thank you, so its equivalent to

val y = this.x
if (y != null) y.doSmth()

right?

[Andreas Sinz]

yes

[ursus]

I knew that, but didnt realize it, thanks a lot

[Andreas Sinz]

let { } doesn't replace if, just use either one of them when its feasible

[ursus]

yea for vals properties its whatever, for vars its useful, thnx