Re: how to skip the next (n) item & continue from (n+1) with a range ? e.g. in File(fn).byLine();

[mw via Digitalmars-d-learn]

On Monday, 22 June 2020 at 20:46:30 UTC, mw wrote:

On Monday, 22 June 2020 at 20:00:50 UTC, Steven Schveighoffer wrote:

I wouldn't recommend it, instead do a while loop:

auto range = File(fn).byLine;

while(!range.empty)
{
   auto line = range.front;
   if(someCond(line)) {
        range.popFrontN(n);

I'm asking this, because here it need to be range.popFrontN(n+1);

i.e. bug-prone

can be fixed by:
   auto line = range.front;
   range.popFront;  // pop immediately

   } else {
        regularProcess(line);
        range.popFront;
   }
}

Thanks.

so `front` is peek, and `popFront` is the pop action whose return type is `void`, why we need two *separate* calls instead of just let `popFront` return T (or do we have another function for this)? i.e if the user forget `popFront`, it will prone to infinite loop bug?

so my question.