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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.

2026/11/3 -The arguments object is a local variable available within all non-arrow functions. You can refer to a function's arguments inside that function by using its ...

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

2026/9/2 -Named parameters are optional unless they're explicitly marked as required . When defining a function, use {param1, param2, …} to specify named parameters. If ...

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 ...

2026/10/23 -Optional and default parameters in JSDoc: square brackets in @param, JavaScript defaults, and what tsc reports when a caller or the function gets it wrong.

2026/11/3 -Generally speaking, a function is a "subprogram" that can be called by code external (or internal, in the case of recursion) to the function.

2026/9/30 -Using Optional Method Arguments. Using optional, named method arguments on your helper functions can make your code easier to read and more self-documenting.

2026/9/6 -I'm writing a service function for a personal project. Right now I have something like export async function createApplicationService( userId, companyName, ...