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