โก
Conduit
Lazy High Performance Streams using Coroutine TS
Conduit is a utility library for building and transforming, ranges and lazy (infinite) iterable sequences.
Conduit's goals are:
๐จ Expressivity๐ถ Composability๐ Performance
These are attained by adopting a monadic interface that leverages zero-cost abstractions.
Install
Download the header-only library bundle from the releases page.
If you are using Buckaroo:
buckaroo add github.com/LoopPerfect/conduit@branch=master
Build
To fetch dependencies (only required for testing and benchmarks):
buckaroo install
To build the library:
buck build :conduit
To run the examples:
buck run examples/primes
buck run examples/fibonacci
# etc...
To run the tests:
buck test //...
Examples
Use co_yield
to define a coroutine and transform it using high-level operators.
using namespace std;
using namespace conduit;
using namespace conduit::operators;
auto fib = []() -> seq<int> {
auto a = 0;
auto b = 1;
while ( true ) {
co_yield a;
tie(a, b) = tuple{a + b, a};
}
};
auto items = fib()
>> take(5)
>> zipWith(range, [](auto x, auto y) {
return tuple{x, y};
});
int vals[] = { 0, 1, 1, 2, 3, 5 };
for(auto [i, n] : items) {
EXPECT_EQ(vals[i], n);
}
Construct elaborate algorithms using higher order operators:
#define RET(X) { return X; }
// sieve of eratosthenes
auto primes = [] {
return range()
>> map([](auto i) RET(3+i*2) ) // create a seqence of odd nums > 2
>> flatMap([primes = vector<int>()](auto c) mutable RET (
primes // divide each candidate by the primes we encountered
>> find([c](auto p) RET (c % p == 0)) // search and stop if divisible
>> count() // find yields at most 1 element, count how many we got (starts with zero)
>> orElse(just(c)) // if we didn't find any, its a prime. yield it
>> find([](auto x) RET (x)) // filter out zeros yielded by find+count or take prime
>> forEach([&](auto p) {
primes.push_back(p); // update list of primes
}) // Note: lifetime of primes-vector is bound to the coroutine
)) >> startsWith(just(2)); // two is the only even prime
};
Support
Currently only clang-7
with -fcoroutines-ts
is supported.
MSVC support should be added in the near future.
Contributions Welcome!
Head over to our issue tracker to get involved in Conduit's development.