Catching panics in Golang

Question

With the following code, if no file argument is given, a panic is thrown for line 9 panic: runtime error: index out of range as expected.

How can I \'catch\

Answer 1

Note that the recover treatment of a panic Execution error (such as attempting to index an array out of bounds trigger) might change with go 1.7 after issue 14965

See CL 21214 and its test:

runtime: make execution error panic values implement the Error interface

Make execution panics implement Error as mandated by Run-time panics (specs), instead of panics with strings.

When you recover a panic error, you would be able to do:

if _, ok := recovered.(runtime.Error); !ok {

---

This is still being evaluated, and as Dave Cheney. mentions:

I don't know what people are currently doing but from my POV this has been broken for a long time and nobody has complained so they are either explicitly relying on the broken behaviour, or nobody cares. Either way I think it's a good idea to avoid making this change.