NOTE: This plugin is included in @babel/preset-env, in ES2021
In
JavaScript
a ||= b;
obj.a.b ||= c;
a &&= b;
obj.a.b &&= c;
Out
JavaScript
var _obj$a, _obj$a2;
a || (a = b);
(_obj$a = obj.a).b || (_obj$a.b = c);
a && (a = b);
(_obj$a2 = obj.a).b && (_obj$a2.b = c);
While using the @babel/plugin-proposal-nullish-coalescing-operator plugin (included in @babel/preset-env)
JavaScript
a ??= b;
obj.a.b ??= c;
JavaScript
var _a, _obj$a, _obj$a$b;
(_a = a) !== null && _a !== void 0 ? _a : (a = b);
(_obj$a$b = (_obj$a = obj.a).b) !== null && _obj$a$b !== void 0
? _obj$a$b
: (_obj$a.b = c);
pnpm add --save-dev @babel/plugin-proposal-logical-assignment-operators
babel.config.json
{
"plugins": ["@babel/plugin-proposal-logical-assignment-operators"]
}
Shell
babel --plugins @babel/plugin-proposal-logical-assignment-operators script.js
JavaScript
require("@babel/core").transformSync("code", {
plugins: ["@babel/plugin-proposal-logical-assignment-operators"],
});
更多建議: