#7828: RebindableSyntax and Arrow ----------------------------------------------+---------------------------- Reporter: AlessandroVermeulen | Owner: Type: bug | jstolarek Priority: normal | Status: new Component: Compiler (Type checker) | Milestone: 7.10.1 Resolution: | Version: 7.6.2 Operating System: Unknown/Multiple | Keywords: Type of failure: GHC rejects valid program | Architecture: Test Case: | Unknown/Multiple Blocking: | Difficulty: Unknown | Blocked By: | Related Tickets: #1537, | #3613 ----------------------------------------------+---------------------------- Comment (by ross): Replying to [comment:37 jstolarek]:

Now I see this was even mentioned in "A New Notation for Arrows" paper. Again there's something I don't understand here. So far I though that stack is an implicit mechanism that is used to pass around values bound using `<-`. But here it seems that the user is allowed to explicitly access the stack. Isn't that a bit risky? The local environment is used to pass around values bound inside the `proc` expression. The stack is used to pass around anonymous values. They can be pushed using application, popped and named in the environment by command lambda, and also manipulated by control operators. The type constraints on operators keep them well behaved.

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