+ #
+ # b = new FlatBuffer.from("12345")
+ # b.capitalize(src="foo")
+ # assert b == "Foo45"
+ #
+ # b = new FlatBuffer.from("preserve my ACRONYMS")
+ # b.capitalize(keep_upper=true)
+ # assert b == "Preserve My ACRONYMS"
+ fun capitalize(keep_upper: nullable Bool, src: nullable Text) do
+ src = src or else self
+ var length = src.length