: (parseh) ( a -- n f ) ( '0': ASCII 0x30 'x': 0x78 0x7830 ) DUP 1+ @ 0x7830 = NOT IF 0 EXIT THEN ( a 0 ) ( We have "0x" prefix ) DUP C@ ( a len ) 0 SWAP 1+ ( len+1 ) 3 DO ( a r ) OVER I + C@ ( a r c ) _ ( a r n ) DUP 0< IF 2DROP 0 UNLOOP EXIT THEN SWAP 4 LSHIFT + ( a r*16+n ) LOOP NIP 1 ;