how to convert data format in mapper

Summary

replace space with ';'

Content

HI All, 

need help in knowing the fuction used for below.

the data  passed from trigger as "ABC DEF" or "ABC DEF XYZ" i want to convert it as "ABC;DEF" ,"ABC;DEF;XYZ", has to replace the space in between with ';' which fuction i can use in mapper 

 

thansk in advance.

Sudheer.