You want lines, so that you may have multiple statements in your lambda. They've given you multiple statements, but using the semicolon instead.

I appreciate that won't work well for all use cases, but it'd eliminate a lot of the pain with the current lambda implementation.

For whatever reason, the Python community declared multiline lambdas as non-pythonic and this project aims to remain pythonic, so they went with semicolons instead.

I'm not a Python developer myself, but if that was the only thing holding you back, then perhaps that reason is now slightly reduced?

If you really need more than one line this will probably work:

  L |> map$(def (x) -> (
    y = 1/x;
    y*(1 - y)
  ))

You can also make multiline python lambdas by using brackets. That is if you can fit your code into an expression.

And it only supports assignment statements and keyword statements. What’s a “keyword statement”?