assert(0) behavior

[via Digitalmars-d]

On Tuesday, 4 August 2015 at 20:21:24 UTC, Walter Bright wrote:
> On 8/3/2015 8:37 PM, Ola Fosheim =?UTF-8?B?R3LDuHN0YWQi?= 
> <ola.fosheim.grostad+dlang at gmail.com> wrote:
>> The input/environment/code distinction does not work very well.
>
> Sure it does. If your user ever sees an assert failure message, 
> your program has a bug in it.

Yes.

> Keep that in mind when designing the code, and the distinction 
> will become clear.

The input/code distinction is too simplistic.

Example 1: It makes perfect sense to assert (or assume) that a 
value from a hardware register or cpu instruction is within 
range. If the assert fires, it is the spec/code that is wrong, 
not the input. So you are testing the specification in the code 
against well defined input.

Example 2: It makes perfect sense to enforce that a return value 
from a plugin library is within range to maintain main program 
integrity and shut out a misbehaving plugin.

And so on.