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<DIV><FONT face=Calibri>Dear all,</FONT></DIV>
<DIV><FONT face=Calibri></FONT> </DIV>
<DIV><FONT face=Calibri>Happy New Year!</FONT></DIV>
<DIV><FONT face=Calibri></FONT> </DIV>
<DIV><FONT face=Calibri>I am learning the Induction Proof over Haskell, I saw
some proofs for the equivalence of two functions will have a case called
'bottom' but some of them do no have. What kind of situation we
should also include the bottom case to the proof? How
about the functions do not have the 'bottom' input such
as:</FONT></DIV>
<DIV><FONT face=Calibri></FONT> </DIV>
<DIV><FONT face=Calibri>foo [] = []</FONT></DIV>
<DIV><FONT face=Calibri>foo (x:xs) = x : (foo xs)</FONT></DIV>
<DIV><FONT face=Calibri></FONT> </DIV>
<DIV><FONT face=Calibri>thank you,</FONT></DIV>
<DIV><FONT face=Calibri></FONT> </DIV>
<DIV><FONT face=Calibri>Raeck</FONT></DIV></BODY></HTML>