Guido van Rossum o khothalelitse ho kenyelletsa li-operator tse tsamaellanang le Python

Guido van Rossum tsebisoa moralo bakeng sa tlhahlobo ea sechaba tobileng bakeng sa ho kenya tšebetsong li-operators tse bapisang mohlala (match le case) ho Python. Ho lokela ho hlokomeloa hore litlhahiso tsa ho eketsa li-operator tse tsamaisanang le mohlala li se li phatlalalitsoe ka 2001 le 2006 (pep-0275, pep-3103), empa li ile tsa hanoa molemong oa ho ntlafatsa moaho oa "haeba ... elif ... ho seng joalo" bakeng sa ho bokella liketane tse nyallanang.

Ts'ebetsong e ncha e tšoana le "match" opareitara e fanoeng ho Scala, Rust, le F #, e bapisang sephetho sa polelo e boletsoeng le lethathamo la lipaterone tse thathamisitsoeng ka har'a li-blocks tse thehiloeng ho "case" operator. Ho fapana le opareitara ea "switch" e fumanehang ho C, Java, le JavaScript, mantsoe a "match" a fana ka tse ling tse ngata. tshebetso e pharaletseng. Hoa hlokomeloa hore basebetsi ba reriloeng ba tla ntlafatsa ho baloa ha khoutu, ho nolofatsa papiso ea lintho tsa Python le ho lokisa liphoso, hape ba eketse ho tšepahala ha khoutu ka lebaka la monyetla oa ho atolosoa. ho hlahloba mofuta o tsitsitseng.

def http_error(boemo):
boemo ba papali:
nyeoe ea 400:
khutlisetsa "Kopo e mpe"
nyeoe 401|403|404:
khutlisa "Ha ea lumelloa"
nyeoe ea 418:
khutla "Ke 'na teapot"
case_:
return "Ho hong hape"

Mohlala, o ka manolla lintho, li-tuples, manane, le tatellano e sa reroang ho kopanya mefuta e ipapisitseng le boleng bo teng. E lumelloa ho hlalosa litempele tse behiloeng, sebelisa maemo a eketsehileng a "haeba" ka har'a template, sebelisa limaske ("[x, y, * rest]"), limmapa tsa bohlokoa / tsa boleng (mohlala, {"bandwidth": b, "latency ”: l} ho ntša "bandwidth" le "latency" le dikishinari), ntša li-subtemplates (":=" opareitara), sebelisa li-constants ho template. Ka litlelaseng, hoa khonahala ho hlophisa boitšoaro bo nyallanang ka mokhoa oa "__match__()".

ho tsoa ho li-dataclass import dataclass

@dataclass
ntlha ea sehlopha:
x:ine
y:ine

def whereis(point):
ntlha ea papali:
Ntlha ea nyeoe(0, 0):
hatisa ("Origin")
Ntlha ea nyeoe(0, y):
hatisa(f"Y={y}")
Ntlha ea nyeoe(x, 0):
hatisa(f"X={x}")
Ntlha ea nyeoe():
print("Sebakeng se seng")
case_:
print("Ha se ntlha")

ntlha ea papali:
case Ntlha(x, y) haeba x == y:
hatisa(f"Y=X ho {x}")
Ntlha ea nyeoe(x, y):
hatisa (f"Eseng ho diagonal")

KHIBEDU, THARA, PUTSOA = 0, 1, 2
'mala o tšoanang:
case .RED:
print("Ke bona khubelu!")
case .REEN:
print("Bojang bo botala")
nyeoe .BLU
E:
print(“Ke ikutloa ke le mothating :(“)

Sehlopha se lokiselitsoe ho hlahlojoa likotopo ka liteko kenngwa tshebetsong tlhahiso e reriloeng, empa mofuta oa ho qetela o ntse o le teng tšohloa. Mohlala nyeheloa Sebakeng sa poleloana "case _:" bakeng sa boleng ba kamehla, sebelisa lentsoe la sehlooho "else:" kapa "default:", kaha "_" maemong a mang e sebelisoa e le phetoho ea nakoana. Hape ho belaetsang ke mokhatlo o hlophisitsoeng oa ka hare, o itšetlehileng ka ho fetolela lipolelo tse ncha ho bytecode tse tšoanang le tse sebelisoang bakeng sa "haeba ... elif ... e 'ngoe" e haha, e ke keng ea fana ka ts'ebetso e lakatsehang ha ho etsoa lipapiso tse kholo haholo.

Source: opennet.ru