# file before.csv before processing.
x,                ABD      # just reorder
y,                BCa      # line with duplicate letters
y,                XZ       # line with spaces, dup col 0 of line before
z                          # all spaces
space.html,       AERS     # multiple spaces
,                          # empty fields
# this is a line comment
bellweather.html, DEFabc   # case-sensitive reorder
abundance.html,   ADEQ     # typically how I use this. The letters are processing options for exceptional files.
font.html,        AELP
activedit.html             # no column 1
addnotify.html,   Z        # only one letter