Re: highlight failed part of isearch input

[Richard Stallman]

    I like this proposal but there is a problem in the patch:

          (when (string-match " +$" m)
             (propertize (substring m (match-beginning 0)) 'face 
'trailing-whitespace))

    This is a no-op.

Yes, if it is used for effect.

                      But maybe it is good to remove this code because the
    failed trailing whitespace is highlighted in the new face isearch-failed.

I don't entirely understand.  What change are you proposing?