1瞭解python2和python3類的區別
python2在2.4以前使用的是經典類, 2.4以後, 使用的是新式類
class Foo:
pass
class Foo(object):
pass
MRO: method resolution order 方法的查找順序
class Base:
pass
class Base1:
def chi():
pass
class Bar(Base, Base1):
pass
b = Bar() # Bar -> Base -> Base1
b.chi()
2. 經典類的MRO 樹形結構的深度優先遍歷 -> 樹形結構遍歷
3. 新式類的MRO C3算法(難點, 重點)
1. 拆分
2. 合併
用頭和身體比較
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class
A:
pass
class
B(A):
pass
class
C(A):
pass
class
D(B, C):
pass
class
E(C, A):
pass
class
F(D, E):
pass
class
M:
pass
class
N(M):
pass
class
P(E, A):
pass
class
X:
pass
class
Q(P,N,X):
pass
class
G(Q, F):
pass
class
H(G, F):
pass
# L(A) = A
# L(B) = B + L(A) + A
# L(C) = C + L(A) + A
# L(D) = D + L(B) + L(C) + BC
# L(E) = E + L(C) + L(A) + CA
# L(F) = F + L(D) + L(E) + DE
# L(M) = M
# L(N) = N + L(M) + M
# L(P) = P + L(E) + L(A) + EA
# L(X) = X
# L(Q) = Q + L(P) + L(N) + L(X) +PNX
# L(G) = G + L(Q) + L(F) + QF
# L(H) = H + L(G) + L(F) + GF
#
#
# L(A) = A
# L(B) = B + L(A) + A # BA
# L(C) = C + L(A) + A # CA
# L(D) = D + L(B) + L(C) + BC # DBCA
# L(E) = E + L(C) + L(A) + CA # ECA
# L(F) = F + L(D) + L(E) + DE # FDBECA
# L(M) = M
# L(N) = N + L(M) + M # NM
# L(P) = P + L(E) + L(A) + EA # PECA
# L(X) = X
# L(Q) = Q + L(P) + L(N) + L(X) +PNX # QPECANMX
# L(G) = G + L(Q) + L(F) + QF # GQPFDBECANMX
# L(H) = H + L(G) + L(F) + GF # HGQPFDBECANMX
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