How can I modify each element of a list while iterating over it in Scala?

Question

I have a List of String declared like this:

var re1_emoticons=""::Nil

Which I have then filled in with emoticons (Strings). I am trying to add a \\ at the beginning of each String in re1_emoticons, modifying the original var.

First attempt:

re1_emoticons.foreach(t=>"""\\""" + t)

Second attempt:

re1_emoticons.foreach(t=>re1_emoticons.indexOf(t)="""\\"""+ t)

Third attempt:

re1_emoticons.foreach(t=>re1_emoticons.indexOf(t):="""\\"""+ t)

However still don't find the way. Is there a correct way to do this?

marstran · Accepted Answer · 2016-09-28 17:02:08Z

6

Use the map-function. It creates a new list with a function applied to each of the items. When you get the new list, you can assign it to the var you already have.

re1_emoticons = re1_emoticons.map(t => """\\""" + t)

answered Sep 28, 2016 at 17:02

marstran

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Nagarjuna Pamu · Accepted Answer · 2016-09-28 17:34:59Z

2

The problem with foreach is it does not return anything. Use map instead of foreach or use for-comprehension syntax.

re1_emoticons = for(emoticon <- re1_emoticons) yield ("""\\""" + emotican)

answered Sep 28, 2016 at 17:34

Nagarjuna Pamu

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