問(wèn)題描述

import sysa = 11init_cnt = sys.getrefcount(a) - 1print 'init', init_cnt####init 22def function(c): print ’in function, count: ’, sys.getrefcount(c) - 1 ####in function, count: 24 print ’函數(shù)調(diào)用，計(jì)數(shù)器增加’, sys.getrefcount(c) - 1 - init_cnt ####函數(shù)調(diào)用，計(jì)數(shù)器增加 2function(a)

問(wèn)題解答

把a(bǔ)當(dāng)參數(shù)傳入到function后被引用了兩次:

for attr in dir(function): print attr, getattr(function, attr)

可以看到參數(shù)a被function這個(gè)對(duì)象中的兩個(gè)屬性分別引用.