if len(exps) == 1: return exps[0]
else:
result = []
for exp in exps:
if isinstance(exp, SpecialCall) and exp.command is Begin:
result += list(exp.args)
else:
result.append(exp)
return Begin(*result)
def Begin_fun(compiler, cont, *exps):
return cps_convert_exps(compiler, exps, cont)
Begin = special(Begin_fun)
@special
def if_(compiler, cont, test, then, else_):
v = compiler.new_var(il.ConstLocalVar('v'))
return test.cps(
compiler,
il.Clamda(
v, il.If(v, then.cps(compiler, cont), else_.cps(compiler, cont))))
def cps_convert_exps(compiler, exps, cont):
v = compiler.new_var(il.ConstLocalVar('v'))
if not exps: return il.PassStatement()
if len(exps) == 1:
def begin(*exps):
exps = tuple(element(e) for e in exps)
if len(exps)==1: return exps[0]
else:
result = []
for exp in exps:
if isinstance(exp, SpecialCall) and exp.command is Begin:
result += list(exp.args)
else:
result.append(exp)
return Begin(*result)
def Begin_fun(compiler, cont, *exps):
return cps_convert_exps(compiler, exps, cont)
Begin = special(Begin_fun)
@special
def if_(compiler, cont, test, then, else_):
v = compiler.new_var(il.ConstLocalVar('v'))
return test.cps(compiler,
il.Clamda(v, il.If(v, then.cps(compiler, cont),
else_.cps(compiler, cont))))
def cps_convert_exps(compiler, exps, cont):
v = compiler.new_var(il.ConstLocalVar('v'))
if not exps: return il.PassStatement()
if len(exps)==1:
return exps[0].cps(compiler, cont)
else:
return exps[0].cps(compiler,
il.Assign(il.parse_state, parse_state),
il.SetBindings(bindings),
fc(il.FALSE))),
il.SetFailCont(il.clamda(v1,
il.SetFailCont(fc),
clause2.cps(compiler, or_cont))),
clause1.cps(compiler, or_cont))
else:
return il.begin(
il.Assign(fc, il.failcont),
il.SetFailCont(il.clamda(v1,
il.SetFailCont(fc),
clause2.cps(compiler, cont))),
clause1.cps(compiler, cont))
or2 = special(or2_fun)
@special
def first_(compiler, cont, clause1, clause2):
v = compiler.new_var(il.ConstLocalVar('v'))
fc = compiler.new_var(il.ConstLocalVar('fc'))
first_cont = il.clamda(v, il.SetFailCont(fc), cont(v))
return il.begin(
il.Assign(fc, il.failcont),
il.append_failcont(compiler, clause2.cps(compiler, first_cont)),
clause1.cps(compiler, first_cont))
def first_p(*exps):
if not exps: raise
elif len(exps)==1: return once(exps[0])
elif len(exps)==2: return first_(*exps)
