这个魔术Javascript如何工作?

这是一个小的javascript,提醒“Hello world”:

゚ω゚ノ=/`m´)ノ~┻━┻//*´∇`*/['_'];o=(゚ー゚)=_=3;c=(゚Θ゚)=(゚ー゚)-(゚ー゚);(゚Д゚)=(゚Θ゚)=(o^_^o)/(o^_^o);(゚Д゚)={゚Θ゚:'_',゚ω゚ノ:((゚ω゚ノ==3)+'_')[゚Θ゚],゚ー゚ノ:(゚ω゚ノ+'_')[o^_^o-(゚Θ゚)],゚Д゚ノ:((゚ー゚==3)+'_')[゚ー゚]};(゚Д゚)[゚Θ゚]=((゚ω゚ノ==3)+'_')[c^_^o];(゚Д゚)['c']=((゚Д゚)+'_')[(゚ー゚)+(゚ー゚)-(゚Θ゚)];(゚Д゚)['o']=((゚Д゚)+'_')[゚Θ゚];(゚o゚)=(゚Д゚)['c']+(゚Д゚)['o']+(゚ω゚ノ+'_')[゚Θ゚]+((゚ω゚ノ==3)+'_')[゚ー゚]+((゚Д゚)+'_')[(゚ー゚)+(゚ー゚)]+((゚ー゚==3)+'_')[゚Θ゚]+((゚ー゚==3)+'_')[(゚ー゚)-(゚Θ゚)]+(゚Д゚)['c']+((゚Д゚)+'_')[(゚ー゚)+(゚ー゚)]+(゚Д゚)['o']+((゚ー゚==3)+'_')[゚Θ゚];(゚Д゚)['_']=(o^_^o)[゚o゚][゚o゚];(゚ε゚)=((゚ー゚==3)+'_')[゚Θ゚]+(゚Д゚).゚Д゚ノ+((゚Д゚)+'_')[(゚ー゚)+(゚ー゚)]+((゚ー゚==3)+'_')[o^_^o-゚Θ゚]+((゚ー゚==3)+'_')[゚Θ゚]+(゚ω゚ノ+'_')[゚Θ゚];(゚ー゚)+=(゚Θ゚);(゚Д゚)[゚ε゚]='\\';(゚Д゚).゚Θ゚ノ=(゚Д゚+゚ー゚)[o^_^o-(゚Θ゚)];(o゚ー゚o)=(゚ω゚ノ+'_')[c^_^o];(゚Д゚)[゚o゚]='\"';(゚Д゚)['_']((゚Д゚)['_'](゚ε゚+(゚Д゚)[゚o゚]+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚ー゚)+(゚Θ゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚ー゚)+((゚ー゚)+(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((o^_^o)+(o^_^o))+((o^_^o)-(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((o^_^o)+(o^_^o))+(゚ー゚)+(゚Д゚)[゚ε゚]+((゚ー゚)+(゚Θ゚))+(c^_^o)+(゚Д゚)[゚ε゚]+(゚ー゚)+((o^_^o)-(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚Θ゚)+(c^_^o)+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚ー゚)+((゚ー゚)+(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+((゚ー゚)+(o^_^o))+(゚Д゚)[゚ε゚]+(゚ー゚)+(c^_^o)+(゚Д゚)[゚ε゚]+(゚Θ゚)+((o^_^o)-(゚Θ゚))+((゚ー゚)+(o^_^o))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+((゚ー゚)+(o^_^o))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((o^_^o)+(o^_^o))+((o^_^o)-(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚ー゚)+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚ー゚)+((o^_^o)-(゚Θ゚))+(゚Д゚)[゚ε゚]+((゚ー゚)+(゚Θ゚))+(゚Θ゚)+(゚Д゚)[゚o゚])(゚Θ゚))('_');

好看的版本:

゚ω゚ノ = /`m´)ノ~┻━┻//*´∇`*/['_'];
o = (゚ー゚) = _ = 3;
c = (゚Θ゚) = (゚ー゚) - (゚ー゚);
(゚Д゚) = (゚Θ゚) = (o^_^o)/(o^_^o);
(゚Д゚) = {
  ゚Θ゚:  '_',
  ゚ω゚ノ: ((゚ω゚ノ==3)+'_')[゚Θ゚],
  ゚ー゚ノ: (゚ω゚ノ+'_')[o^_^o-(゚Θ゚)],
  ゚Д゚ノ: ((゚ー゚==3)+'_')[゚ー゚]
};
(゚Д゚)[゚Θ゚] = ((゚ω゚ノ==3)+'_')[c^_^o];
(゚Д゚)['c'] = ((゚Д゚)+'_')[(゚ー゚)+(゚ー゚)-(゚Θ゚)];
(゚Д゚)['o'] = ((゚Д゚)+'_')[゚Θ゚];
(゚o゚)=(゚Д゚)['c'] + (゚Д゚)['o'] + (゚ω゚ノ + '_')[゚Θ゚] + ((゚ω゚ノ==3) + '_')[゚ー゚] + ((゚Д゚) + '_')[(゚ー゚) + (゚ー゚)] + ((゚ー゚==3) + '_')[゚Θ゚] + ((゚ー゚==3) + '_')[(゚ー゚) - (゚Θ゚)] + (゚Д゚)['c'] + ((゚Д゚) + '_')[(゚ー゚) + (゚ー゚)] + (゚Д゚)['o'] + ((゚ー゚==3) + '_')[゚Θ゚];
(゚Д゚)['_'] = (o^_^o)[゚o゚][゚o゚];
(゚ε゚) = ((゚ー゚==3) + '_')[゚Θ゚] + (゚Д゚).゚Д゚ノ + ((゚Д゚) + '_')[(゚ー゚) + (゚ー゚)] + ((゚ー゚==3) + '_')[o^_^o-゚Θ゚] + ((゚ー゚==3) + '_')[゚Θ゚] + (゚ω゚ノ+'_')[゚Θ゚];
(゚ー゚) += (゚Θ゚);
(゚Д゚)[゚ε゚] = '\\';
(゚Д゚).゚Θ゚ノ = (゚Д゚+゚ー゚)[o^_^o-(゚Θ゚)];
(o゚ー゚o) = (゚ω゚ノ+'_')[c^_^o];
(゚Д゚)[゚o゚] = '\"';
(゚Д゚)['_']((゚Д゚)['_'](゚ε゚+(゚Д゚)[゚o゚]+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚ー゚)+(゚Θ゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚ー゚)+((゚ー゚)+(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((o^_^o)+(o^_^o))+((o^_^o)-(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((o^_^o)+(o^_^o))+(゚ー゚)+(゚Д゚)[゚ε゚]+((゚ー゚)+(゚Θ゚))+(c^_^o)+(゚Д゚)[゚ε゚]+(゚ー゚)+((o^_^o)-(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚Θ゚)+(c^_^o)+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚ー゚)+((゚ー゚)+(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+((゚ー゚)+(o^_^o))+(゚Д゚)[゚ε゚]+(゚ー゚)+(c^_^o)+(゚Д゚)[゚ε゚]+(゚Θ゚)+((o^_^o)-(゚Θ゚))+((゚ー゚)+(o^_^o))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+((゚ー゚)+(o^_^o))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((o^_^o)+(o^_^o))+((o^_^o)-(゚Θ゚))+(゚Д゚)[゚ε゚]+(゚Θ゚)+((゚ー゚)+(゚Θ゚))+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚Θ゚)+(゚ー゚)+(゚ー゚)+(゚Д゚)[゚ε゚]+(゚ー゚)+((o^_^o)-(゚Θ゚))+(゚Д゚)[゚ε゚]+((゚ー゚)+(゚Θ゚))+(゚Θ゚)+(゚Д゚)[゚o゚])(゚Θ゚))('_');

JSFiddle

从这里获取:http://codegolf.stackexchange.com/a/24041/17049

任何人都有任何想法如何工作?我甚至不看到该代码中的警报。

在仔细观察代码之前,你必须知道,因为JavaScript 1.5 identifiers允许不仅包含ASCII字符,还包含Unicode字符。

在这种情况下,许多有趣的序列只是标识符。在通过更简单的标识符交换这些标识符并去除不必要的注释和括号之后,代码看起来如下:

a = /`m´)ノ~┻━┻/['_'];
o = b = _ = 3;
c = d = b-b;
e = d = o^_^o/o^_^o;
e = {
  d: '_',
  a: ((a==3)+'_')[d],
  h: (a+'_')[o^_^o-d],
  i: ((b==3)+'_')[b]
};
e[d]   = ((a==3)+'_')[c^_^o];
e['c'] = (e+'_')[b+b-d];
e['o'] = (e+'_')[d];
f      = e['c']+e['o']+(a+'_')[d]+((a==3)+'_')[b]+(e+'_')[b+b]+((b==3)+'_')[d]+((b==3)+'_')[b-d]+e['c']+(e+'_')[b+b]+e['o']+((b==3)+'_')[d];
e['_'] = (o^_^o)[f][f];
g      = ((b==3)+'_')[d]+e.i+(e+'_')[b+b]+((b==3)+'_')[o^_^o-d]+((b==3)+'_')[d]+(a+'_')[d];
b      += d;
e[g]   = '\\';
e.j    = (e+b)[o^_^o-d];
obo    = (a+'_')[c^_^o];
e[f]   = '\"';
e['_'](e['_'](g+e[f]+e[g]+d+b+d+e[g]+d+(b+d)+b+e[g]+d+b+(b+d)+e[g]+d+((o^_^o)+(o^_^o))+((o^_^o)-d)+e[g]+d+((o^_^o)+(o^_^o))+b+e[g]+(b+d)+(c^_^o)+e[g]+b+((o^_^o)-d)+e[g]+d+d+(c^_^o)+e[g]+d+b+(b+d)+e[g]+d+(b+d)+b+e[g]+d+(b+d)+b+e[g]+d+(b+d)+(b+(o^_^o))+e[g]+b+(c^_^o)+e[g]+d+((o^_^o)-d)+(b+(o^_^o))+e[g]+d+(b+d)+(b+(o^_^o))+e[g]+d+((o^_^o)+(o^_^o))+((o^_^o)-d)+e[g]+d+(b+d)+b+e[g]+d+b+b+e[g]+b+((o^_^o)-d)+e[g]+(b+d)+d+e[f])(d))('_');

现在我们可以一次评估每个语句:

> a = /`m’)ノ〜┻━┻/ [‘_’]求值为a = undefined
> o = b = _ = 3分配o,b和_整数3
> c = d = b-b指定c和d为整数0
分配e和d整数1(o ^ _ ^ o求值为3 XOR 3 XOR 3,这产生3)
> e = {d:’_’,a:(a == 3)’_’)[d],h:(a’_’)[o ^ _ ^ od],i: 3)’_’)[b]}分配对象{d:’_’,a:’a’,h:’d’,i:’e’}
> e [d] =((a == 3)’_’)[c ^ _ ^ o]分配e [1]
> e [‘c’] =(e’_’)[b b-d]分配e [‘c’]字符串’c’
> e [‘o’] =(e’_’)[d]分配e [‘o’]字符串’o’

这只是设置和以下变量设置:

a = undefined
b = 3
c = 0
d = 1
e = {
    1: "f",
    a: "a",
    c: "c",
    d: "_",
    h: "d",
    i: "e",
    o: "o"
}

下一个语句是第一个构造东西的语句:

f = e['c'] +             // => "c"
    e['o'] +             // => "o"
    (a+'_')[d] +         // => "undefined_"[1] = "n"
    ((a==3)+'_')[b] +    // => "false_"[3]     = "s"
    (e+'_')[b+b] +       // => "object_"[6]    = "t"
    ((b==3)+'_')[d] +    // => "true_"[1]      = "r"
    ((b==3)+'_')[b-d] +  // => "true_"[2]      = "s"
    e['c'] +             // => "c"
    (e+'_')[b+b] +       // => "object_"[6]    = "t"
    e['o'] +             // => "o"
    ((b==3)+'_')[d];     // => "true"[1]       = "r"

所以f =“构造函数”。在下一个语句中,“constructor”用于检索函数:

e['_'] = (o^_^o)[f][f]

这相当于(3).constructor.constructor,它产生function Function,所以:

e['_'] = Function

这个函数函数是特殊的,因为可以通过将参数传递给函数体代码来动态构造函数:

f = Function("alert(1)")
// equivalent to
f = function() { alert(1) }

我将跳过下面的几个语句,只是写结果变量和值:

a = undefined
b = 4
c = 0
d = 1
e = {
    1: "f",
    _: Function,
    a: "a",
    c: "c",
    constructor: "\"",
    d: "_",
    h: "d",
    i: "e",
    j: "b",
    o: "o",
    return: "\\"
}
f = "constructor"
obo = "u"

最后一个语句做最后的工作:

e['_'](e['_'](g+e[f]+e[g]+d+b+d+e[g]+d+(b+d)+b+e[g]+d+b+(b+d)+e[g]+d+((o^_^o)+(o^_^o))+((o^_^o)-d)+e[g]+d+((o^_^o)+(o^_^o))+b+e[g]+(b+d)+(c^_^o)+e[g]+b+((o^_^o)-d)+e[g]+d+d+(c^_^o)+e[g]+d+b+(b+d)+e[g]+d+(b+d)+b+e[g]+d+(b+d)+b+e[g]+d+(b+d)+(b+(o^_^o))+e[g]+b+(c^_^o)+e[g]+d+((o^_^o)-d)+(b+(o^_^o))+e[g]+d+(b+d)+(b+(o^_^o))+e[g]+d+((o^_^o)+(o^_^o))+((o^_^o)-d)+e[g]+d+(b+d)+b+e[g]+d+b+b+e[g]+b+((o^_^o)-d)+e[g]+(b+d)+d+e[f])(d))('_');

这相当于:

Function(Function( … )(1))('_')

长表达式构建以下字符串:

return"\141\154\145\162\164\50\42\110\145\154\154\157\40\127\157\162\154\144\42\51"

转义字符串求值:

alert("Hello World")

这个返回代码被传递给Function,它创建一个匿名函数,如:

function anonymous() {
    return"\141\154\145\162\164\50\42\110\145\154\154\157\40\127\157\162\154\144\42\51";
}

我们知道,这等价于:

function anonymous() {
    return"alert(\"Hello World\")";
}

此函数然后以1作为参数执行,返回结果字符串:

alert("Hello World")

然后再次将其传递给Function,这将创建一个新的匿名函数:

function anonymous() {
    alert("Hello World");
}

最后,此函数也使用“_”作为参数调用。

http://stackoverflow.com/questions/22588223/how-does-this-magic-javascript-work

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