title: Assign name to a substring in a loop importing raster files
body: <p>I'm importing some raster files from a PostgreSQL connection into R in a loop. I want to assign my newly gained rasters automatically to a variable whose name is derived from the input variable like this: <code>substring(crop, 12)</code></p>
  
  <pre><code>crop &lt;- "efsa_capri_barley"
  ras &lt;- readGDAL(sprintf("PG:dbname='' host='' port='' user='' schema='' table='%s' mode=2", crop))
  paste0(substring(crop, 12)) &lt;- raster(ras, 1)
  </code></pre>
  
  <p>What function do I have to use that R recognizes the result of substring() as a character string and not as the function itself? I was thinking about paste() but it doesn't work.
  Probably this question has already been asked but I couldn't find a proper answer.</p>