Remove last character from string. Swift language

Question

How can I remove last character from String variable using Swift? Can\'t find it in documentation.

Here is full example:

var expression = \"45+22\"
e         


        

Answer 1

Use the function advance(startIndex, endIndex):

var str = "45+22"
str = str.substringToIndex(advance(str.startIndex, countElements(str) - 1))