r - disable all chunk evaluation but keep inline evaluation -

i want disable chunk evaluation keep inline evaluation via \sexpr. setting eval globally false this

  \documentclass{article}     \begin{document}     <<setup, include=false>>=    opts_chunk$set(eval= false)    @     \sexpr{"is not displayed"} bummer.    \end{document} 

also affects \sexpr.

p.s.: searched subsets of [knitr],\sexpr, eval. hope formatting correct

p.s.: don't want set eval 1.