Hello. I have a code like: ```"one ".trim() "two ".trim() "three ".trim()``` I would like to improve...

# announcements

[Vitali Plagov]

Hello.
I have a code like:

"one ".trim()
"two ".trim()
"three ".trim()

I would like to improve it with use of scope functions like run, with, etc. Can I do with them something like this:

<scope_function> {
  "one ",
  "two ",
  "three ".
}.trim()

?

[LeoColman]

I'm not sure that this exactly is possible with a scope function

[LeoColman]

You want to reduce the calls to trim, but they're being used on different objects

[SiebelsTim]

listOf + map is relatively close to your pseudocode

[LeoColman]

scoping functions are useful when we want to to a lot of operations on one object and want to specify how we scope it

[LeoColman]

You might want to go

listOf("one ", "two ", "three ").map { it.trim() }

[LeoColman]

As @SiebelsTim said

[Vitali Plagov]

And in this case if for some reason it fails on a second object, will it continue further or it will exit?

[SiebelsTim]

Fail meaning it throws an exception? It will not continue.

[Vitali Plagov]

Yes, throwing an exception in the middle of the list

[LeoColman]

For you to continue you would have to handle the exception

listOf(...).map { try {it.trim()} catch(e: Exception) { .. }}

[Vitali Plagov]

Though…. in my real case, if it fails in the middle and exits, then it’s fine, I think.

[LeoColman]

but by exiting we mean that it will throw an exception

[Vitali Plagov]

Yes, I understand that. It’s fine to throw an exception. It’s even a desired behaviour

[Vitali Plagov]

Thanks @LeoColman & @SiebelsTim

[wbertan]

You could use an Extension on Collections:

private fun Collection<String>.trim(): Collection<String> = map(String::trim)

    @Test
    fun asas1() {
        val result = listOf(
            "one ",
            "two ",
            "three "
        ).trim()
        val expectedResult = listOf(
            "one",
            "two",
            "three"
        )
        assertEquals(expectedResult, result)
    }

    @Test
    fun asas2() {
        val result = setOf(
            "one ",
            "two ",
            "three "
        ).trim()
        val expectedResult = listOf(
            "one",
            "two",
            "three"
        )
        assertEquals(expectedResult, result)
    }

[LeoColman]

And then you could use a extension function

fun Collection<String>.trim() = this.map { it.trim() }

[Vitali Plagov]

Yes, also a good solution!

[Dico]

Wow, I suppose the test case is appreciated, I hope some assumptions can be made sometimes though 😅👌