$$

There is a special form of the let statement in which no variable is specified (and “let” is not used). This form is provided for convenience, especially in the REPL.

Customer[id > 100] //sets the $$ variable

This stores the result of the query in a special variable called “$$”. Note that the “$$” variable is actually updated after every let statment. $$ represents the value of the most recent let statement.

let z = Customer[id > 100] //sets z and $$