Tom's Two-up Two-down

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Today Has an "a"

We can use the logical && and || operators to determine whether to invoke a function depending on an expression's truthy/falsy value. Here is a simple example:

  • The day of the week includes the letter "a", and I need to blog
  • Either I already blogged today (stop evaluating), or I need to blog

And this is how that looks in JavaScript:

const blog = () => {
  console.log('I need to blog');
};

let todayHasAnA = (today) => {
  today.includes('a') && blog();
};

todayHasAnA('Thursday');
// "I need to blog"

let blogToday = (blogged) => {
  blogged || blog();
};

blogToday(false);
// "I need to blog";