Understanding the distinctions among variables in typescript

Can someone explain the difference in Typescript between
"!option" and "option"? It seems like they are not equivalent.

const limit = !options.limit || options.limit === NaN ? 0 : options.limit

Answer №1

After reviewing your updated code snippet:

const limit = !options.limit || options.limit === NaN ? 0 : options.limit
  • If options.limit is deemed "falsy," it will assign a value of 0 to limit. Otherwise, the value of options.limit will be used.
  • The inclusion of the second condition checking for NaN is redundant since NaN is inherently falsy and covered by the preceding !options.limit check.
  • It's important to note that comparing options.limit === NaN will never evaluate to true, even if options.limit itself is NaN. To accurately check for NaN, utilize isNaN() or Number.isNaN().

In essence, your current implementation can be simplified to:

const limit = options.limit || 0.

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