active eq 0 0 mark true active eq s X s Y mark eq X Y active eq X Y mark false active inf X mark cons X inf s X active take 0 X mark nil active take s X cons Y L mark cons Y take X L active length nil mark 0 active length cons X L mark s length L mark eq X1 X2 active eq X1 X2 mark 0 active 0 mark true active true mark s X active s X mark false active false mark inf X active inf mark X mark cons X1 X2 active cons X1 X2 mark take X1 X2 active take mark X1 mark X2 mark nil active nil mark length X active length mark X eq mark X1 X2 eq X1 X2 eq X1 mark X2 eq X1 X2 eq active X1 X2 eq X1 X2 eq X1 active X2 eq X1 X2 s mark X s X s active X s X inf mark X inf X inf active X inf X cons mark X1 X2 cons X1 X2 cons X1 mark X2 cons X1 X2 cons active X1 X2 cons X1 X2 cons X1 active X2 cons X1 X2 take mark X1 X2 take X1 X2 take X1 mark X2 take X1 X2 take active X1 X2 take X1 X2 take X1 active X2 take X1 X2 length mark X length X length active X length X active 1 eq 2 0 0 mark 1 true 0 s 1 false 0 inf 1 cons 2 take 2 nil 0 length 1 INNERMOST ./TRS/TRCSR/inn/Ex1_GL02a_iGM.trs