Scope functions

Context object: this or it

this

run, apply, with refer to the context object as a lambda receiver.

Operate on the object members: call its functions or assign properties.

it

let, also refer to the context object as a lambda argument.

Easier for reading, object used as an argument in function calls and multiple variables in a block.

Return value

context object

Can continue chaining function calls on the same object after apply,also .

lambda result

run, let,with can assign result to a variable.

run does the same as with, but invokes as let.