• Jeremy DeHaan (4/4) May 05 2016 In core.exception, we have a lovely function called
• tsbockman (12/17) May 05 2016 From the spec
• Jeremy DeHaan (2/15) May 06 2016 Oh, interesting. That makes sense, thanks.

Jeremy DeHaan <dehaan.jeremiah gmail.com> writes:

In core.exception, we have a lovely function called 
onInvalidMemoryOperationError(). This function is marked as 
nothrow (plus other annotations). This function literally does 
nothing except throwing an error. How can it be marked as nothrow?

tsbockman <thomas.bockman gmail.com> writes:

On Friday, 6 May 2016 at 02:57:59 UTC, Jeremy DeHaan wrote:
 In core.exception, we have a lovely function called 
 onInvalidMemoryOperationError(). This function is marked as 
 nothrow (plus other annotations). This function literally does 
 nothing except throwing an error. How can it be marked as 
 nothrow?

 From the spec 
(https://dlang.org/spec/function.html#nothrow-functions):
     "Nothrow functions can only throw exceptions derived from 
class Error."

Throwing an Error is, for many purposes, considered fundamentally 
different than throwing an Exception because Error objects aren't 
meant to be caught by user code. Throwing an Error is supposed to 
just be a way of crashing the program with a nice message and 
stack trace.

A key benefit of this distinction, is that it enables the use of 
`assert()` statements in `nothrow` code.

Jeremy DeHaan <dehaan.jeremiah gmail.com> writes:

On Friday, 6 May 2016 at 03:24:23 UTC, tsbockman wrote:
 On Friday, 6 May 2016 at 02:57:59 UTC, Jeremy DeHaan wrote:
 [...]

 From the spec 
 (https://dlang.org/spec/function.html#nothrow-functions):
     "Nothrow functions can only throw exceptions derived from 
 class Error."

 Throwing an Error is, for many purposes, considered 
 fundamentally different than throwing an Exception because 
 Error objects aren't meant to be caught by user code. Throwing 
 an Error is supposed to just be a way of crashing the program 
 with a nice message and stack trace.

 A key benefit of this distinction, is that it enables the use 
 of `assert()` statements in `nothrow` code.

Oh, interesting. That makes sense, thanks.