jsでアロー関数またはラムダ式の練習

'use strict';

const p = console.log;
const caller = (arg, callback) => callback(arg);
const square = (x) => x * x;
p(caller(6, square));

'use strict';

const p = console.log;

const caller = (arg, callback) => callback(arg);

const square = (x) => x * x;

p(caller(6, square));

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