The first example that Ayrton started with. There exists a called
function that returns a std::expected, and the user wants for the
control flow to continue in the calling function if it does get the
expected type, but return immediately if it gets the unexpected type.
 This description even encapsulates my thoughts on this feature in
that note that I didn't have to say anything else about the called
function, only that it returned a std::expected. I think P2561
addresses the use-case better.

This proposal feels like exceptions, just using a different mechanism
(and is more syntactically invasive).

On Fri, Aug 1, 2025 at 6:52 AM Iúri Chaer via Std-Proposals
<std-proposals_at_[hidden]> wrote:
>
> > Not all return paths in the callable should cause the caller to immediately return.
>
> What's the usage scenario you have in mind? The initial example from the thread looks like it suffers from the same type of ergonomic constraint that keeps me from using monadic functions more frequently, which doesn't require that sort of complexity... I have to agree with the others who compared that form of the proposal with exceptions, it's hard to reason about control flow in the presence of something like that.
>
> On Fri, 1 Aug 2025 at 14:07, Sebastian Wittmeier via Std-Proposals <std-proposals_at_[hidden]> wrote:
>>
>> -----Ursprüngliche Nachricht-----
>> Von: Andre Kostur via Std-Proposals <std-proposals_at_[hidden]>
>>
>>
>>
>> >Not all return paths in the callable should cause the caller to immediately return.
>>
>>
>> >I’m still thinking that the callable shouldn’t have to know about this, and it should be entirely within the caller’s domain as to whether to >return immediately or not.
>>
>>
>>
>>
>>
>> Then why not create a special command to invoke the callable.
>>
>> The caller can decide, whether to use this command or not..
>>
>>
>>
>>
>>
>> OTOH should this work the same as exceptions?
>>
>> Why not use the same or similar language constructs?
>>
>> Probably the in-between functions need to know more about, which exceptions can be thrown.
>>
>>
>>
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