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2026/8/22 -Optional parameters allow a JavaScript function to work even when some arguments are not provided. They make functions more flexible and reusable.

2026/5/22 -The optional chaining (?.) operator accesses an object's property or calls a function. If the object accessed or function called using this operator is ...

2026/9/6 -I assume that the parameters are truly optional, in that you do still want the option of setting them on this call? Seems like you would just create a class ...

2026/10/23 -Put square brackets around the parameter's name in its @param tag. If the parameter has a default, write the default in the JavaScript itself: price.js price.ts

2026/9/23 -Optional parameters allow functions to be called without providing values for every parameter, making them more flexible. · Optional parameters can be omitted ...

2026/9/24 -Mark a TypeScript parameter optional with ?, give it a default value, or collect any number of arguments with a rest parameter. Covers the order rules, omitted ...

2026/1/7 -If I want to run some code that requires an integer variable to be a certain ... Is there a way to make a parameter optional without giving it a default value?

2026/10/15 -Optional Parameters​. You can also have optional parameters by adding a question mark ? after the name of the parameter and before the colon : . 1function ...

2026/8/24 -TypeScript optional parameters and default parameters, explained with a real decision framework — Playwright examples, common mistakes, and SDET interview ...