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2 points by bogomipz 6116 days ago | link | parent

Most of the values in math expressions are in the form of variables. How do you handle that? Stick a dummy number in front like this?

  (0 + x * y * scale)
The compiler will optimize that away, right?


4 points by cadaver 6116 days ago | link

The variables/sub-expressions are first evaluated completely, only then infix analysis will happen. It's exactly like with lists:

  (= somelist '(1 2))
  ...
  (somelist 1)
works just like

  ('(1 2) 1)
does.

As to your second argument, the +-*/ operators are passed as first-class functions, so, there shouldn't be any optimization happening. Worst thing that can happen is that the compiler doesn't understand literal numbers in functional position, or arithmetic operators applied to first-class functions, and signals an error.

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4 points by eds 6116 days ago | link

Assuming x, y and scale are numbers, just

  (x * y * scale)
should do the trick. As cadaver said, the arguments are evaluated completely before infix evaluation. So you can also do

  (x * y * (sqrt z))
or

  (x * Y * (sqrt (t * u + v)))

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2 points by bogomipz 6116 days ago | link

Ah ok, in that case this is no less than brilliant! :)

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