You want to find `toReplace` in `list` and replace it with `

Question

You want to find `toReplace` in `list` and replace it with `replacement` Because the code doesn t require an exact match right now

Daniel · Answer

Yep this is only a very simplified example you can be sure that `toReplace` is part of the `list`

karelpeeters · Answer

```replaceInList listOf 1 2 1 5 2 listOf 1 5 2 listOf 6 ```

Daniel · Answer

The result would be listOf 1 2 6

karelpeeters · Answer

But that s not what your example code does right

Daniel · Answer

I hope I got the example right the first sublist would be `1 2` then `+ 6` and the last sublist yeah would throw an index out of bounds exception I simplified a bit too much it seems Thank you for your reply

karelpeeters · Answer

Ah I wasn t even thinking about that the main problem is that it only looks at the first and last elements for a match Even the size doesn t matter

Daniel · Answer

Maybe I am thinking wrong here but the sizes shouln t matter So you could go with `listOf 1 2 3 4 ` replace `listOf 2 3 ` with `listOf 6 7 8 ` or `listOf 6 ` and should end up with `listOf 1 6 7 8 4 ` or `listOf 1 6 4 ` so any replacement should be possible For the `toReplace` you can be sure that it is part of the `list`

karelpeeters · Answer

Yes but your code right now doesn t necessarily find the correct position for `toReplace` in `list` because it only checks the first and last positions The size of `toReplace` and the matched part of `list` don t even have to match

Daniel · Answer

Ohhh now I understand sorry In the original code the matching is done over identity So you can be sure that the right element is found

nkiesel · Answer

I think what you are trying to say is in the original code the list does not contain any duplicate values As soon as you have duplicates the code might not do what you want Consider original list is ` 1 1 1 2 2 2 ` and you want to replace ` 1 2 ` with ` 3 ` I think you want ` 1 1 3 2 2 ` but your code would produce ` 3 2 2 ` instead But even that is not good enough because `replaceInList listOf 1 2 3 4 5 listOf 4 2 listOf 0 ` would produce ` 1 2 3 0 3 4 5 ` and `replaceInList listOf 1 2 3 4 5 listOf 1 5 listOf 0 ` would produce ` 0 `

nkiesel · Answer

a valid solution assuming you only want to replace the fist match would be ``` fun replaceInList list List lt Int gt toReplace List lt Int gt replacement List lt Int gt List lt Int gt val i = list windowed toReplace size indexOfFirst it == toReplace return if i == 1 list else list take i + replacement + list drop i + toReplace size ```