Actually, it's to allow for non-NUL terminated strings. A good example is when using a String supplied by a scripting language such as Ruby or JavaScript. Nor

Actually, it's to allow for non-NUL terminated strings. A good example is when using a String supplied by a scripting language such as Ruby or JavaScript. Normally, you might need to copy the string to add a NUL byte, or request that the scripting engine provide a NUL terminated string (which might result in the same action performed). Using this optional approach, a potential copy of the data can be avoided.