Functional Programming & Efficient Tools for D.
In Rust, we can use functional programming anywhere because same speed is guaranteed by zero cost abstraction. But in D, we can find functional programming is much slower than OOP or procedural programming. In FPTools, it is also guaranteed like Rust by hand written functions.
- Add
dependenciesindub.json
// In dub.json
{
"dependencies": {
"fptools": "~>0.0.2"
},
}import dtools.fp;
void main() {
mixin FP!long; // You can choose any type to use FP (double, string, int, long and etc.)
Pipe p; // Declare pipeline
p.input(seq(1,100)); // Input sequence
p.proc( // Write Procedures
map(x => 2 * x), // map (Haskell like)
takeWhile(x => x < 100), // takeWhile (Haskell like)
map(x => x / 2), // map (Haskell like)
take(40), // take (Haskell like)
drop(10), // drop (Haskell like)
dropWhile(x => x < 30), // dropWhile (Haskell like)
reduce((x,y) => x * y) // reduce (Haskell like)
);
p.output[0].writeln; // output function exports result as sequence
}