why does this error out?

[lobo via Digitalmars-d-learn]

On Tuesday, 10 November 2015 at 14:25:19 UTC, steven kladitis 
wrote:
> On Tuesday, 10 November 2015 at 05:14:29 UTC, lobo wrote:
>> On Tuesday, 10 November 2015 at 04:34:22 UTC, Cauterite wrote:
>>> Here's the output I get (DMD v2.068.2):
>>>
>>> [1, 3, 10, 12, 21, 30, 100, 102, 111, 120, 201, 210]
>>> core.exception.AssertError at std\range\package.d(4603): 
>>> Assertion failure
>>
>> iota.front() is complaining the range is empty from this line.
>>
>>     harshads.filter!(h => h > 1000).front.writeln;
>>
>> your hardas has no values > 1000 so the filter is empty. 
>> hardwas was seeded with iota(1,256), so the maximum value will 
>> be 252.
>>
>> bye,
>> lobo
>
>
> with dmd 2.069
> I always get
> --> [1
> and then the error no matter what I canhe that line to.

Hmm, that's different to what I get. On linux 64 bit with dmd 
2.069 I get this:

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 18, 20, 21, 24, 27, 30, 36, 
40, 42]
core.exception.AssertError at std/range/package.d(4691): Assertion 
failure


Note the assertion is same as before; hardas has no values > 252 
so filter!(h => h < 1000) results in an empty range.

bye,
lobo