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ASSIGN

The ASSIGN keyword is what variable and function assignments in pipe operator syntax are implicitly translated to. The below expression:

hn <| https://news.ycombinator.com |

Is equivalent to the following expression:

ASSIGN hn https://news.ycombinator.com

As seen above, you can view the ASSIGN keyword as being semantically similar to a SET keyword in postgres or, when contrasting to the <| notation, the functional prefix alternative to <| being an infix operator.