I can't imagine how (b) could be a "yes". Different callbacks are naturally used in different contexts. Sometimes it makes sense for a callback to return a value, other times it doesn't. And sometimes (like Catalyst), the framework is generic enough that the framework designer can't know in advance whether a return value is expected from a given callback or not.

All that aside, I lean towards "no" on (a) regardless. The entire concept of issuing a warning for calling a sub in the wrong context rubs me the wrong way on a rather deep level. I can't identify exactly why, but it's probably connected to the fact that "doing something that doesn't make sense to the module's author" does not necessarily imply "doing something wrong".

In reply to Re: Best practices for warnings about wrong context by dsheroh
in thread Best practices for warnings about wrong context by vsespb

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