def cnum(c, args):
""" usage: (cnum, <name>, <number of bits>, <value>)
defines a constant number
"""
name, nbits, val = deparen(args[0]), deparen(args[1]), deparen(args[2])
ans = ['list', *binrep(val, nbits)]
c.variables[name] = ans
return ans
def defnum(c, args):
""" usage: (defnum, <name>, <number of bits>)
to access the number: (num <name>)
"""
name, nbits = deparen(args[0]), deparen(args[1])
ans = ['list', *[c.junkvar() for i in range(nbits)]]
c.variables[name] = ans
return ans
def exactly_one(c, args):
params = [deparen(arg) for arg in args]
if len(params) == 0:
return c.F
if len(params) == 1:
return params[0]
else:
hlf = len(params) // 2
return [
'|', ['&', ['e1', *params[:hlf]], ['~', ['|', *params[hlf:]]]],
['&', ['e1', *params[hlf:]], ['~', ['|', *params[:hlf]]]]
]
def mac_at(c, args):
return at(deparen(args[0]), [deparen(arg) for arg in args[1:]])
def slice_macro(c, args):
lst = c.expr_tree(args[0])
i = deparen(args[1])
j = deparen(args[2])
return lst[i + 1:j + 1]
def index(c, args):
lst = c.expr_tree(args[0])
i = deparen(args[1])
return lst[i + 1]
def num(c, args):
return c.variables[deparen(args[0])]