Question: I need to convert string to letter case (proper case or title case), is there any default function on Groovy support for this or I need to manual sub string convert first character?

Answer: 
Until i know there is no such a function or method but i use to do it with this sentence

```
assert "John Doe" == "john dOE".tokenize(" ")*.toLowerCase()*.capitalize().join(" ")

```

I hope it help you
I got it, here is solution for those who needed

```
def capitalize(s) { s[0].toUpperCase() + s[1..-1].toLowerCase() }
caps = "man OF stEEL".replaceAll(/\w+/) { w -> capitalize(w) }

```