How to define a constant literal in F#

Question

In C#, I do this:

 public const double PAPER_SIZE_WIDTH = 8.5 * 96; 

What is the best way to define this global constant in F#?

This fails:

  [<Literal>]
  let PaperSizeWidth = 8.5*96.0  

Error: This is not a valid constant expression

TIA

Answer 1

Arithmetic is not yet supported for numeric literals in F#. Instead, you have to provide the final value explicitly:

[<Literal>]
let PaperSizeWidth = 816.0

However, every value is immutable by default in F#, so this might be good enough, depending on your needs:

let PaperSizeWidth = 8.5 * 96.0