Sometimes we may want to exit the knitting process early, and completely
ignore the rest of the document. This function provides a mechanism to
terminate knit().
Usage
knit_exit(append)
Arguments
append
a character vector to be appended to the results from
knit() so far; by default, it is \end{document} for LaTeX
output, and </body></html> for HTML output to make the output
document complete; for other types of output, it is an empty string
Value
Invisible NULL. An internal signal is set up (as a side
effect) to notify knit() to quit as if it had reached the end of the
document.