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Postings from February 2018
I wrote: >I'd be satisfied if the real error at least were the first one emitted. Looking more closely, the reason why the real error isn't emitted first is that it's queued up through the qerror() system. This is a deliberate move to collect up multiple compilation errors, so that multiple errors can be reported even if errors are being reported by means other than emitting a message to stderr. For example, an eval() that encounters multiple compilation errors will yield a $@ that contains multiple concatenated error messages. (And indeed, multiple errors do occur with List::Lazy.) The reason why some other messages appear before the errors is that the earlier messages aren't errors, they're warnings. These go straight to stderr as they arise, rather than being collected with the errors. All of these bits of behaviour are individually intentional, but they have the undesirable effect of losing synchronisation between the warning stream and the error stream. This can't be fixed without some fairly big change to the way compile-time diagnostics are managed. We could perhaps abandon the queuing of errors, aborting compilation immediately on the first error; in this case that would lead to emitting the "syntax error" message and nothing else. Doing that would inevitably garner complaints about situations in which multiple error messages are actually helpful. Any approach around shuffling the order in which messages are emitted would be hideously complicated. Maybe we could do something else to distinguish between warnings and errors, to draw greater attention to the first error even if it's not the first message emitted. We can't fix this for 5.28. -zeframThread Previous | Thread Next