No, unless you have a third MVar to control access to the first two (which doesn't really scale, and is the entire point of STM!) On 10 November 2016 at 12:34, Lian Hung Hon wrote:

Dear cafe,

Is it possible to atomically modify two MVars? (I know it can be done with TVars)

Regards, Hon

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El 10 nov 2016, a las 04:34, Lian Hung Hon escribió:

Dear cafe,

Is it possible to atomically modify two MVars? (I know it can be done with TVars)

Or TMVars, if you haven't seen those. tom