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Pyline
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Pyline is an esoteric subset of Python 3.10 where the whole source file has to be a single expression. The walrus operator is available, making Pyline fairly easy to use. For a challenge, see Pyline Classic.
Idioms
| Python | Pyline |
|---|---|
var = 5 |
var := 5 |
if 1 + 1 == 2:
print("Hello, ")
print("World! ")
|
1 + 1 == 2 and (
print("Hello, "),
print("World! ")
)
(
print("Hello, "),
print("World! "),
) if 1 + 1 == 2 else None
(
print("Hello, ") and 0 or
print("World! ")
) if 1 + 1 == 2 else None
|
if i == 1:
...
elif i == 2:
...
else:
...
|
(
...
) if i == 1 else (
...
) if i == 2 else (
...
)
|
for i in range(10):
print(i)
|
all( (print(i),) for i in range(10) ) [(
print(i),
) for i in range(10)]
next(
None for i in range(10)
if not (
print(i) and 0 or
True
)
)
|
while cond:
print(1)
|
all( cond and (print(1),) for _ in iter(int,1) ) [(
print(1),
) for _ in iter(lambda: cond, False)]
next(
None for _ in __import__("itertools").count()
if not (
print(1) and 0 or
cond
)
)
|
def add(a, b):
res = a + b
print(res)
return res
|
add := lambda a, b: (
res := a + b,
print(res),
res
)[-1]
add := lambda a, b: (
(res := a + b) and 0 or
print(res) and 0 or
res
)
|
arr[0] += 1 |
arr.insert(0, arr.pop(0) + 1) arr.__setitem__(0, arr[0] + 1) |
obj.var = 5 |
setattr(obj, "var", 5) |
import sys |
sys := __import__("sys")
|
class Glass(object):
_area = 406,
def getarea(self):
return self._area
|
Glass := type("Glass", (object,), dict(
_area = 406,
getarea = lambda self: self._area,
)),
|
raise err |
(_ for _ in "_").throw(err) |
try:
print(1 / 0)
except BaseException as err:
print(err)
|
(
CD := (
__import__("contextlib")
.ContextDecorator,
),
sml_catcher := type("Catcher", CD, dict(
__enter__ = lambda self: self,
__exit__ = lambda self, *err: (
setattr(self, "err", err)
or True
),
)),
catch := sml_catcher(),
catch(lambda: (
print(1 / 0)
))(),
print(catch.err)
)
|
Examples
Hello World
print("hello world")
Quine
(lambda s:print(f'{s}({chr(34)}{s}{chr(34)})'))("(lambda s:print(f'{s}({chr(34)}{s}{chr(34)})'))")
A shorter one:
print((s:='print((s:=%s)%%s)')%s)
Or without walrus operator:
print((lambda s:s%s)('print((lambda s:s%%s)(%r))'))
A longer one:
(
s:=[],
s.append(112),
s.append(114),
s.append(105),
s.append(110),
s.append(116),
s.append(40),
s.append(39),
s.append(40),
s.append(39),
s.append(41),
s.append(44),
s.append(10),
s.append(112),
s.append(114),
s.append(105),
s.append(110),
s.append(116),
s.append(40),
s.append(39),
s.append(115),
s.append(61),
s.append(91),
s.append(93),
s.append(44),
s.append(39),
s.append(41),
s.append(44),
s.append(10),
s.append(91),
s.append(10),
s.append(32),
s.append(40),
s.append(10),
s.append(32),
s.append(32),
s.append(112),
s.append(114),
s.append(105),
s.append(110),
s.append(116),
s.append(40),
s.append(39),
s.append(115),
s.append(46),
s.append(97),
s.append(112),
s.append(112),
s.append(101),
s.append(110),
s.append(100),
s.append(40),
s.append(39),
s.append(44),
s.append(101),
s.append(110),
s.append(100),
s.append(61),
s.append(39),
s.append(39),
s.append(41),
s.append(44),
s.append(10),
s.append(32),
s.append(32),
s.append(112),
s.append(114),
s.append(105),
s.append(110),
s.append(116),
s.append(40),
s.append(120),
s.append(44),
s.append(101),
s.append(110),
s.append(100),
s.append(61),
s.append(39),
s.append(39),
s.append(41),
s.append(44),
s.append(10),
s.append(32),
s.append(32),
s.append(112),
s.append(114),
s.append(105),
s.append(110),
s.append(116),
s.append(40),
s.append(39),
s.append(41),
s.append(44),
s.append(39),
s.append(41),
s.append(10),
s.append(32),
s.append(41),
s.append(10),
s.append(102),
s.append(111),
s.append(114),
s.append(32),
s.append(120),
s.append(32),
s.append(105),
s.append(110),
s.append(32),
s.append(115),
s.append(93),
s.append(44),
s.append(10),
s.append(91),
s.append(112),
s.append(114),
s.append(105),
s.append(110),
s.append(116),
s.append(40),
s.append(99),
s.append(104),
s.append(114),
s.append(40),
s.append(120),
s.append(41),
s.append(44),
s.append(101),
s.append(110),
s.append(100),
s.append(61),
s.append(39),
s.append(39),
s.append(41),
s.append(10),
s.append(102),
s.append(111),
s.append(114),
s.append(32),
s.append(120),
s.append(32),
s.append(105),
s.append(110),
s.append(32),
s.append(115),
s.append(93),
s.append(44),
s.append(10),
s.append(112),
s.append(114),
s.append(105),
s.append(110),
s.append(116),
s.append(40),
s.append(39),
s.append(41),
s.append(39),
s.append(41),
print('('),
print('s=[],'),
[
(
print('s.append(',end=''),
print(x,end=''),
print('),')
)
for x in s],
[print(chr(x),end='')
for x in s],
print(')')
)
Truth machine
(
count:=__import__("itertools").count,
i:=input(":"),
[
print('1',end="") for _ in count()
] if i == '1'
else (
print('0')
)
)
The walrus operator is only used here for readability; the entire expression can be given without it:
[print("1", end="") for _ in __import__("itertools").count()] if input(":") == "1" else print("0")
A version that doesn't use __import__
[print(1,end="")for _ in iter(lambda:0,1)]if input(":")=="1"else print(0)
A shorter one:
input()=="1"and{print(end="1")for _ in iter(set,0)}or print(0)
Rule 110 (Turing-completeness proof)
(
count:=__import__("itertools").count,
grb:=__import__("random").getrandbits,
SIZE:=150,
board:=[[bool(grb(1)) for _ in range(SIZE)],],
[
(
old_board:=board[0].copy(),
print("".join('.#'[i] for i in board[0])),
board.__setitem__(0,[
(
l:=old_board[(i-1)%SIZE],
r:=old_board[(i+1)%SIZE],
(
bool(110 & 2**(4*l+2*t+r))
)
)[-1]
for i,t in enumerate(board[0])
])
)
for _ in count()
]
)
Brainfuck interpreter
Written by User: YufangTSTSU:
(
brainfuck_inpreter := lambda code: (
imports := __import__,
whiler := (type("whiler", (object,), {
"__init__": lambda s,f: setattr(s,"f",f) if callable(f) else \
(_ for _ in ()).throw(TypeError(f"{f.__class__.__name__} object is not callable")),
"__iter__": lambda s: s,
"__next__": lambda s: None if s.f() else next(iter(())),
"__repr__": lambda s: f"<whiler object with {s.f}>"
})),
code_index := [0],
tape := [0],
tape_index := [0],
input_store := [""],
[(
{
"+":lambda: tape.insert(tape_index[0], (tape.pop(tape_index[0]) + 1) % 256),
"-":lambda: tape.insert(tape_index[0], (tape.pop(tape_index[0]) - 1) % 256),
">":lambda: (
tape_index.append(tape_index.pop() + 1),
None if tape_index[0] < len(tape) else tape.append(0)
),
"<":lambda: tape_index.append(tape_index.pop() - 1) \
if tape_index[0] > 0 else tape.insert(0, 0),
".":lambda: print(chr(tape[tape_index[0]]), end="", flush=True),
",":(lambda: (
tape.pop(tape_index),
tape.insert(tape_index, int.from_bytes(imports("msvcrt").getche()))
)) if "-getch" in imports("sys").argv else (lambda: (
(
input_store.pop(),
input_store.append(input())
) if input_store == [""] else None,
tape.pop(tape_index[0]),
tape.insert(tape_index[0], ord(input_store[0][0]) % 256),
input_store.append(input_store.pop()[1:]),
)),
"[":lambda: (
sml_index := code_index[0],
brackets := 1,
[(
sml_index := sml_index + 1,
brackets := brackets + {"[":1,"]":-1}.get(code[sml_index],0)
) for __ in whiler(lambda: brackets != 0)],
code_index.pop(),
code_index.append(sml_index)
) if not tape[tape_index[0]] else None,
"]":lambda: (
sml_index := code_index[0],
brackets := -1,
[(
sml_index := sml_index - 1,
brackets := brackets + {"[":1,"]":-1}.get(code[sml_index],0)
) for __ in whiler(lambda: brackets != 0)],
code_index.pop(),
code_index.append(sml_index)
) if tape[tape_index[0]] else None
}.get(code[code_index[0]], lambda: None)(),
code_index.append(code_index.pop()+1),
) for _ in whiler(lambda: len(code) > code_index[0])]
),
None
)
Another written by User:DGCK81LNN; takes both the program and the input from standard input, with the start of the input indicated by a !.
(lambda cod, _, inp:
(lambda *, _cp = 0, _mp = 0, _ip = 0, _mem = {}, _inp = inp .encode(), _out = b"": next(
__import__("sys").stdout.buffer.write(_out) and None or None
for _ in __import__("itertools").count()
if not (
_mem.__setitem__(
_mp,
((_mem[_mp] if _mp in _mem else 0) + (1 if cod[_cp] == "+" else -1 if cod[_cp] == "-" else 0)) & 255
) and 0 or
(_mp := _mp + (1 if cod[_cp] == ">" else -1 if cod[ _cp] == "<" else 0)) and 0 or
(
(_cp := (lambda si, *, _d = 0:
next(i
for i in (range(si, len(cod)) if cod[si] == "[" else range(si, -1, -1))
if cod[i] in "[]" and ((_d := _d + (1 if cod[i] == "[" else -1)) == 0)
)
)(_cp))
if cod[_cp] in "[]" and bool(_mem[_mp] if _mp in _mem else 0) == bool(cod[_cp] == "]")
else 0
) and 0 or
(
(_out := _out + bytes((_mem[_mp],))) if cod[_cp] == "."
else _mem.__setitem__(_mp, _inp[_ip]) and 0 or (_ip := _ip + 1) if cod[_cp] == "," and _ip < len(_inp)
else 0
) and 0 or
(_cp := _cp + 1) < len(cod)
)
))()
)(*__import__("sys").stdin.read().partition("!"))
Another written by User: Jan jelo
( program:=list(input())+['@'], ltape:=[0],rtape:=[0], pc:=0,i:=0,state:=0, INC:=lambda:ltape.append((ltape.pop()+1)%256), DEC:=lambda:ltape.append((ltape.pop()-1)%256), IN:=lambda:ltape.append(ord(input())%256), LS:=lambda:(a:=ltape[-1], ltape.pop() if len(ltape)>1 else ..., rtape.append(a) ), RS:=lambda:(a:=rtape[-1], rtape.pop() if len(rtape)>1 else ..., ltape.append(a) ), [( ( (LS(), state:=1) if program[pc]=='<' else (RS(), state:=1) if program[pc]=='>' else (INC(),state:=1) if program[pc]=='+' else (DEC(),state:=1) if program[pc]=='-' else (IN(),state:=1) if program[pc]==',' else (print(chr(ltape[-1]),end=''),state:=1) if program[pc]=='.' else ( (i:=0,state:=2) if ltape[-1]==0 else (state:=1) ) if program[pc]=='[' else ( (i:=0,state:=3) if ltape[-1]!=0 else (state:=1) ) if program[pc]==']' else (state:=4) if program[pc]=='@' else... ) if state==0 else ( state:=0, pc:=pc+1 ) if state==1 else ( ( i:=i-1, (state:=0) if i==0 else (pc:=pc+1) ) if program[pc]=='[' else ( i:=i+1, (state:=0) if i==0 else (pc:=pc+1) ) if program[pc]==']' else (pc:=pc+1) ) if state==2 else ( ( i:=i-1, (state:=0) if i==0 else (pc:=pc-1) ) if program[pc]=='[' else ( i:=i+1, (state:=0) if i==0 else (pc:=pc-1) ) if program[pc]==']' else (pc:=pc-1) ) if state==3 else ... ) for _ in iter(lambda:state!=4,0)] )
Another one, still written by User:YufangTSTSU:
(I:=open(0).read().partition("!"),c:=I[0],I:=[*I[2]],d:={},s:=[],[(s:=s+[i])if c=="["else c=="]"and(d:=d|{i:s[-1],s.pop():i})for i,c in enumerate(c)],p:=0,t:=[i:=0]*30000,s:=t.__setitem__,[(s(p,t[p]+1&255)if c=="+"else s(p,t[p]-1&255)if c=="-"else print(end=chr(t[p]))if c=="."else s(p,ord(I.pop(0)))if c==","else(p:=p+1)if c==">"else(p:=p-1)if c=="<"else(c=="]"and t[p]or c=="["and t[p]<1)and(i:=d[i]),i:=i+1)for c in iter(lambda:i<len(c)and c[i],0)])
Spaced version:
(
I := open(0).read().partition("!"),
c := I[0], I := [*I[2]],
d := {}, s := [],
[
(s := s + [i]) if c == "[" else
c == "]" and (d := d | {i: s[-1], s.pop(): i})
for i, c in enumerate(c)
],
p := 0, t := [i := 0] * 30000,
s := t.__setitem__,
[(
s(p, t[p] + 1 & 255) if c == "+" else
s(p, t[p] - 1 & 255) if c == "-" else
print(end = chr(t[p])) if c == "." else
s(p, ord(I.pop(0))) if c == "," else
(p := p + 1) if c == ">" else
(p := p - 1) if c == "<" else
(c == "]" and t[p] or c == "[" and t[p] < 1) and (i := d[i]),
i := i + 1
) for c in iter(lambda:i < len(c) and c[i], 0)]
)
Another by User: Jan jelo
(i:=input,p:=i(),c:=0,l:=[0],r:=[0],
s:=lambda l,i,e:l.__setitem__(i,e),
a:=lambda l,e:l.append(e),
[(o:=p[c],ll:=len(l)-1,lr:=len(r)-1,
lf:=l[-1],rf:=r[-1],
(
(
(o=='+')and s(l,ll,(lf+1)%256)),
(o=='-')and s(l,ll,(lf-1)%256),
(o=='<')and(a(r,lf),(ll>0)and l.pop()),
(o=='>')and(a(l,rf),(lr>0)and r.pop()),
(o=='.')and(print(chr(lf),end='',flush=1)),
(o==',')and(l.pop(),a(l,ord(i()or chr(lf))%256)),
c:=c+1
)
if not o in '[]'else
(b:=c,j:=1,m:=[-1,1][o=='['],
[(b:=b+m,n:=p[b],
(n=='[')and(j:=j+m),
(n==']')and(j:=j-m)
)
for _ in iter(lambda:j,0)],
(c:=b)if [lf,lf==0][(m+1)//2] else(c:=c+1)
)
)
for _ in iter(lambda:len(p)>c,0)]
)
Another by User: Jan jelo, convert bf code into Pyline code then evaluate
(g:='t.get(c,0)',
s:=lambda x:f't.__setitem__(c,{x}),',
o:=lambda x:{
'+':s(f'{g}+1&255'),
'-':s(f'{g}-1&255'),
'<':'c:=c-1,',
'>':'c:=c+1,',
',':s('ord((input()or chr(0))[0])'),
'.':f'print(chr({g}),end="",flush=1),',
'[':'[(',
']':f')for _ in iter(lambda:{g},0)],'
}.get(x,'...,'),
eval(f'(t:=dict(),c:=0,{"".join(map(o,input()))})')
)
And another by User:YufangTSTSU, using evals:
(lambda c,_,g,S,G:eval(",".join(f"{S+G}+1&255)|{S+G}-1&255)|print(end=chr({G}))|{S}ord(g[q:=q+1]))|(p:=p+1)|(p:=p-1)|[(0|)for _ in iter(lambda:{G},0)]".split("|")["+-.,<>[]".index(i)]for i in c),dict(t={},p=0,g=g,q=-1)))(*input().partition("!"),"t.__setitem__(p,","t.get(p,0)")