javascript - How to define a recursive object with a single expression? -


for example, given object:

let foo = {foo:1}; let bar = {a:foo,b:foo};

we can define bar single expression writing as:

let bar = (($0)=>({a:$0={foo:1},b:$0}))()

however, given object:

let o = {a:'perfect'}; o.circle = o;

is possible recreate structure of o single expression?

this won't work:

(($0)=>($0={a:"perfect",circle:$0}))()

because circle nested , $0 has been defined yet.

unless want solve getter properties, assignment unavoidable.

there kinds of ways that, within single expression:

let o = (o = {a:'perfect'}).circle = o;

but recommend focus on clarity , use iife instead:

const o = (function(){     const x = {a:'perfect'};     x.circle = x;     return x; }()); // more first solution without mutable `o` variable: const o = (x => x.circle = x)({a:'perfect'});

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