[bpicolo]

Why is the `var` keyword required in function arguments if it's dynamically typed and there's no other possible option?

[billytetrud]

So you don't create variables when you typo a variable name. Declarations are an error catching mechanism

[fasquoika]

This is a complete guess, but maybe so they can treat it the same way as normal variable declarations

[ateesdalejr]

Might be. Probably reusing the same pattern matching code in function definitions.