The code for the four bit manipulation functions is shown below, and some explanation follows the
listings.
Code for bitset() - set a bit
bitset(x,b)
Func
©(wordOrList,bit#) set bit#
©18may01/dburkett@infinet.com
local k,msg,type
"bitset() err"→msg
gettype(x)→type
when(type="NUM",when(b<0 or b>31,msg,exact(x or 2^b)),when(type="LIST",when(b<0
or b>32*dim(x)-1,msg,augment(left(x,k-1),augment({exact(x[k] or
2^(b-(k-1)*32))},right(x,dim(x)-k)))|k=1+intdiv(b,32)),msg))
EndFunc
Code for bitclr() - clear a bit
bitclr(x,b)
Func
©(wordOrList,bit#) clear bit#
©21may01/dburkett@infinet.com
local k,msg,type
"bitclr() err"→msg
gettype(x)→type
when(type="NUM",when(b<0 or b>31,msg,exact(x and not 2^b)),when(type="LIST",
when(b<0 or b>32*dim(x)-1,msg,augment(left(x,k-1),augment({exact(x[k] and not
2^(b-(k-1)*32))},right(x,dim(x)-k)))|k=1+intdiv(b,32)),msg))
EndFunc
Code for bitnot() - invert a bit
bitnot(x,b)
Func
©(wordOrList,bit#) invert bit#
©21may01/dburkett@infinet.com
local k,msg,type
"bitnot() err"→msg
gettype(x)→type
when(type="NUM",when(b<0 or b>31,msg,exact(x xor 2^b)),when(type="LIST",when(b<0
or b>32*dim(x)-1,msg,augment(left(x,k-1),augment({exact(x[k] xor
2^(b-(k-1)*32))},right(x,dim(x)-k)))|k=1+intdiv(b,32)),msg))
EndFunc
Code for bittst() - test bit status
bittst(x,b)
3 - 26
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