\documentclass[12pt]{article}
\usepackage{xspace}
\usepackage{hyperref}
\newcommand{\x}{x\xspace}

\begin{document}
  \section{Implicite space: \x world}
  \section{Explicite spaces: \x\ world \x\space world \x~world}
  \section{\x.+\x,+\x!+\x?+\x-+\x:+\x;+\x/+last-\x}
  \makeatletter
  \section{~|~~|~~~|~~~~|~~~~~|~~~~|~~~|~~|~}
  \section{\x()(\x) }
  \section{Italic correction: [\x\/]}
  \section{::Nothing follows:}
  \section{}
  \section{\x}
\end{document}