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Comment by vosper | Hacker News Reader

I have been interested in OCaml for a while, and this is a nice piece. One question, though - some of the examples start like this:

- :

Is that the prompt from the OCaml REPL (does OCaml have a REPL)?

EDIT: I think I misread things - it's the output from the examples that has the "- :" prefix, so I'm guessing it is REPL output.

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That's what the prompt answers back.

   # 3;;
   - : int = 3
   # fun x -> x*x;;
   - : int -> int = <fun>

You can think of '-' as meaning 'the last evaluated expression' and ':' as meaning 'has the type'. So the OCaml repl replies to your input by saying something like 'the last evaluated expression has the type ...'.

The grey boxes are the input to the REPL. You should be able to just copy paste the contents of any of the boxes. The green boxes are the output of the REPL.

# let x = 5;; val x : int = 5 #

that's what the REPL looks like on my end

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