I'm trying to use the Nullish coalescing assignment operator (??=) in NodeJS, it is possible?
const setValue = (object, path, value) => {
const indices = {
first: 0,
second: 1
},
keys = path.replace(new RegExp(Object.keys(indices).join('|'), 'g'), k => indices[k]).split('.'),
last = keys.pop();
keys
.reduce((o, k, i, kk) => o[k] ??= isFinite(i + 1 in kk ? kk[i + 1] : last) ? [] : {}, object)[last] = value;
return obj;
}
est.js:9
.reduce((o, k, i, kk) => o[k] ??= isFinite(i + 1 in kk ? kk[i + 1] : last) ? [] : {}, object)
^
SyntaxError: Unexpected token '?'
at wrapSafe (internal/modules/cjs/loader.js:1067:16)
at Module._compile (internal/modules/cjs/loader.js:1115:27)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1171:10)
at Module.load (internal/modules/cjs/loader.js:1000:32)
at Function.Module._load (internal/modules/cjs/loader.js:899:14)
at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
at internal/main/run_main_module.js:17:47
The error means your version of Node does not yet have support for the ??=
operator.
Check out the versions which support it on node.green :
The node version you are using doesn't support the nullish coalescing assignment operator.
It's possible for node version v15.14+.
The rewrite for something like
a.greeting ??= "hello"
in node <v15.14 is:
a.greeting = a?.greeting ?? 'hello'
Maybe it does help someone:]
You could replace logical nullish assignment ??=
o[k] ??= isFinite(i + 1 in kk ? kk[i + 1] : last) ? [] : {}
with an assignment with logical OR ||
o[k] = o[k] || (isFinite(i + 1 in kk ? kk[i + 1] : last) ? [] : {})
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