OCaml: Matching with any negative -

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is there way pattern matching match value negative number? not matter negative number need match negative.

i have accomplished want simple code: 

let y = if(n < 0) 0 else n in    match y   0 -> []   | _ -> [x] @ clone x (n - 1)

but want eliminate if statement , check case in match statement

yes, use guard:

match n     _ when n < 0 -> []   | _ -> [x] @ clone x (n - 1)

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