if "!LF!" NEQ "!LF:~0,1!" echo Error "Linefeed definition is defect, probably multiple invisble whitespaces at the line end in the definition of LF"
FOR /F "delims=" %%n in ("!LF!") do (
echo Error "Linefeed definition is defect, probably invisble whitespaces at the line end in the definition of LF"
)