You can abuse "panic" to implement exceptions in Golang the way you can abuse "longjmp" to do that in C. The purpose of "panic" isn't for general-purpose exceptions. It's to panic the program.
But correct code must assume that any function you call might throw; which is why you should use defer blocks e.g. to release resources, instead of C-style "cleanup at the bottom of the function". (Defer is also prettier IMHO)
It's idiomatically correct to ignore panics and let them take the whole program down with a crash. A panic indicates that your program is already doing extremely incorrect things. Rare is the program where picking itself up and continuing a possible Sorcerer's Apprentice mode rampage is better than just stopping and telling you what needs fixing.
Or raising?
That's just terminology. The behaviors of c++/java/python exceptions and Go panics are similar regardless of the name the keyword has in those language:
The execution is suspended, the stack unwound until the first handler, the handler has access to a value that is "thrown". Stack information is preserved in order to print meaningful stack traces.
C++/java/python have syntax sugar that performs a pattern match on the thrown object to decide whether to handle it or bubble it up, while in Go you do it manually, but other that that I don't see much of a difference in the mechanics of them to justify being so pedantic about the naming of the action.
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You can abuse "panic" to implement exceptions in Golang the way you can abuse "longjmp" to do that in C. The purpose of "panic" isn't for general-purpose exceptions. It's to panic the program.
Note that this mechanic is used in the golang standard library and works great as a catchall: http://golang.org/src/pkg/text/template/exec.go#L93
It's clear you shouldn't throw.
But correct code must assume that any function you call might throw; which is why you should use defer blocks e.g. to release resources, instead of C-style "cleanup at the bottom of the function". (Defer is also prettier IMHO)
It's idiomatically correct to ignore panics and let them take the whole program down with a crash. A panic indicates that your program is already doing extremely incorrect things. Rare is the program where picking itself up and continuing a possible Sorcerer's Apprentice mode rampage is better than just stopping and telling you what needs fixing.
You're not "throwing". You're "panicking".
Or raising? That's just terminology. The behaviors of c++/java/python exceptions and Go panics are similar regardless of the name the keyword has in those language:
The execution is suspended, the stack unwound until the first handler, the handler has access to a value that is "thrown". Stack information is preserved in order to print meaningful stack traces.
C++/java/python have syntax sugar that performs a pattern match on the thrown object to decide whether to handle it or bubble it up, while in Go you do it manually, but other that that I don't see much of a difference in the mechanics of them to justify being so pedantic about the naming of the action.