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From: Alexey Egorov <alex.only.d@gmail.com>
Date: Fri, 18 Aug 2017 19:09:44 +0500
Message-ID: <CAJannG6JRWv_BqTR_pDMLWhxmOYFtSHLWR7pOCU_G2j_qaPWHg@mail.gmail.com>
To: caml users <caml-list@inria.fr>
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Subject: [Caml-list] strange type error with -principal

Hello,

I'm getting very confusing error when compiling with -principal:

> Error: This expression has type int op
>       but an expression was expected of type 'a
>       This instance of int is ambiguous:
>       it would escape the scope of its equation

What is the "instance of int"?

Here is the code - https://pastebin.com/T74haahx
I'm mostly confused by the fact that changing pattern from (op, idx)
to simple value binding eliminates this error.

Thanks!