EasyLambda – parallel data processing with modern C++ (opens in new tab)

It's very common when chaining lots of operations, each of which transforms the result of the previous one (functional style). I've seen tons of Scala code do it. Writing it all in one line would be quite the unreadable mess.

Here is an article around this style (ExpressionBuilder) by martin fowler: http://martinfowler.com/bliki/ExpressionBuilder.html

It lets you pass around a FooObject/FooContext and offers you a lot of the powers of a DSL while still being boring, stock BarLanguage. I find it to be very helpful for making declarative-style APIs.

[flagged] And why is this downvoted? Do the downvoters disagree with the assertion that hellofunk hasn't seen this idiom before?

Really, dang, you can remove posts like mine but you do nothing to address the real problem here.

One can still use TBB inside the functions to make use of it alongside getting MPI parallelism from easyLambda.

Moreover, easyLambda has data flows, map, reduce which in a way improves the way programs are written and composed. There are no classes to be declared for anything. It has many syntactic sugars, for column selection, control over parallelism, i/o etc. I personally like the style of coding in it for various problems, keeping parallelism aside.

By skimming through the code, this seems to have the same data-flow model as Intel's TBB, but extended to distributed memory configurations using MPI as backend.

One big difference is that easyLamdba has MPI parallelism, i.e. you can run it on lots of machines, whereas TBB is for a single machine.

Thanks for your interest. There are indeed no function pointers, no void pointers, no preprocessor hacks, no wild type-casting involved anywhere in the library. This is completely compile time type-safe. Still, the kind of things you can do would be a far cry for all the hacks with those shoddy pointers. There are a lot of features like column manipulation, passing vector of a values for multiple rows and just a value for a single row etc. that make composability and ease of use way better. All of these features are implemented using template meta programming and traits available in modern C++. The language has become quite impressive from what we used to think of. You must check it out.

A map/reduce/rise take a template parameter which can be of any class type and library has nothing to do what a function object or function does in the function body. The function just need to take in the arguments that the prior unit passes it and return something. I don't think there will be any problem if one uses any other library to perform computation inside a function, even if some library does not work out of the box, I'm pretty positive it can be done with little tinkering. I hope this makes things clear.