Re: Filter a Range Based on a Passed In Variable
On Saturday, 20 January 2018 at 19:09:28 UTC, Adam D. Ruppe wrote: On Saturday, 20 January 2018 at 19:04:06 UTC, jsako wrote: I want to be able to filter a range based on a variable known at runtime. Something like this: [code] int id = getFilterID(); auto filteredRange = filter!(a => a.id == id)(rangeToBeFiltered); [/code] This doesn't seem to be possible, however as .filter only takes unary predicates. I tried: That should actually work. What exactly happened when you ran that literal code above? ... Huh. The code I posted was a simplified case of what I actually have and like a fool I didn't test it first. You're absolutely right, the above code does work. Color me embarrassed. In the actual code, I kept getting DMD saying "...does not match template declaration filter(alias predicate) if (is(typeof(unaryFun!predicate)))". I think it may be a scoping issue? I'll have to look closer at it. Thanks for the help! Sorry I wasted your time. At least this pointed me in the right direction to find out what is really going on.
Re: Filter a Range Based on a Passed In Variable
On Saturday, 20 January 2018 at 19:04:06 UTC, jsako wrote: I want to be able to filter a range based on a variable known at runtime. Something like this: [code] int id = getFilterID(); auto filteredRange = filter!(a => a.id == id)(rangeToBeFiltered); [/code] This doesn't seem to be possible, however as .filter only takes unary predicates. I tried: That should actually work. What exactly happened when you ran that literal code above?
Filter a Range Based on a Passed In Variable
I want to be able to filter a range based on a variable known at runtime. Something like this: [code] int id = getFilterID(); auto filteredRange = filter!(a => a.id == id)(rangeToBeFiltered); [/code] This doesn't seem to be possible, however as .filter only takes unary predicates. I tried: [code] filterString = "a.id == " ~ to!string(id); filter!filterString(rangeToBeFiltered); [/code] But that also doesn't work. Is there another range algorithm that should be used in this case? Do I roll my own?
