Patrick Thomson ac543651ee Add NFData instances to enable more accurate benchmarking. ... Because we're getting serious about benchmarking in the run-up to Windrose, it's time to bring in the `deepseq` package to ensure that benchmarks can fully evaluate the result of a test case. The `deepseq` package provides an `NFData` typeclass: ``` class NFData a where rnf :: a -> () ``` Instances use the `seq` combinator to ensure that the argument to `rnf` is fully evaluated, returning (). If there is a `Generic` instance for `a`, the implementation can be omitted. This patch adds NFData for every syntax node, graph vertex, environment data structures, and exceptions. It is long, but the work is very straightforward, so don't panick. The benchmark suite (`stack bench`) now produces more accurate results. The benchmarks previously mimicked `rnf` by calling `show` on the result of an evaluation or graph construction; now that we have actual `NFData` instances we can use the `nfIO` combinator from criterion. This has sped up the evaluation benchmarks and reduced their memory consumption, while it has slowed down the call graph benchmarks, as those benchmarks weren't evaluating the whole of the graph. Unfortunately, this patch increases compile times, as we have to derive a few more Generic instances. I wish this weren't the case, but there's little we can do about it now. In the future I have some plans for how to reduce compile time, and I bet that those gains will at least nullify the speed hit from this patch. Now that we have NFData instances for every data type, we can start benchmarking assignments, in preparation for fixing #2205. This patch also pulls in updates to `effects` and `fastsum` that add appropriate NFData instances for the data they vend.		2018-10-17 14:08:47 -04:00
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bench-fixtures	add ruby	2018-03-07 19:47:23 -05:00
evaluation	Add NFData instances to enable more accurate benchmarking.	2018-10-17 14:08:47 -04:00