title: How to use F string in R to save as xlsl along side date
body: <p>How do I use the F string in r</p>
  <p>I have a data frame that I want to save as xlsl but the data frame is something that wound continuously be dropping day by day</p>
  <p>for example</p>
  <p>yesterday report would be analyzed today</p>
  <p>so I want to automate the report in such a way that the data frame name would also carry yesterday date</p>
  <p>see below</p>
  <p><code>yesterday &lt;- Sys.date () -1</code> (this gives yesterday date)</p>
  <p>now, I want to include the yesterday variable to generate the report as excel</p>
  <p>I have tried</p>
  <p>F string in r using gsub library
  <code>write_xlsx(ecosftp, &quot;Mydata_vtu_autoreport_{yesterday}.xlsx&quot;)</code> .. but its not working</p>
  <p>I want the result to look like this so that anytime he save the report, it will always save as system date minus 1 which gives yesterday date</p>
  <pre><code>write_xlsx(ecosftp, &quot;Mydata_vtu_autoreport_2021-10-09.xlsx&quot;)
  </code></pre>