just put the fieldline of format in quote will fix the issue. 
format STDOUT_TOP = 
@<<<<<<<<<<<<<<<     @||||||||||    @|||||    @|||||
"User                  Command        CPU      Mem%"
.
$^ = 'STDOUT_TOP';
format STDOUT = 
@<<<<<<<<<<<<<<<     @||||||||||    @#####    @#####
$user,                $cmd,          $cpu,     $mem
.

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In reply to Re^2: Format Syntax error on "." by bimleshsharma
in thread Format Syntax error on "." by jcain

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