Crate pushgen

Push-style design pattern for processing of ranges and data-streams.

This is a Rust-based approach to the design pattern described by transrangers. While the discussion linked targets C++, the same basic principle of pull-based iterators applies to Rust as well (with some modifications since Rust doesn’t have a concept of an end iterator like C++ does).

Example

for item in data.iter().filter(|x| *x % 2 == 0).map(|x| x * 3) {
    process(item);
}

can be rewritten as

use pushgen::{SliceGenerator, GeneratorExt};
// Assume data is a slice
SliceGenerator::new(&data).filter(|x| *x % 2 == 0).map(|x| x * 3).for_each(process);

Features

std: Enable boxing and trait implementations for types that requires std. If this feature is disabled, pushgen is no_std. This is enabled by default.

test: Enable test tools that can be used to test generators and adaptors. This is disabled by default.

Performance

I make no performance-claims, however there are some benchmarked cases where the push-based approach wins over the iterator approach, but I have made no attempts to analyze this in any depth.

Re-exports

• pub use traits::FromGenerator;
• pub use traits::Generator;
• pub use traits::GeneratorExt;
• pub use traits::IntoGenerator;
• pub use traits::ReverseGenerator;
• pub use generators::from_fn;
• pub use generators::from_iter;
• pub use generators::SliceGenerator;

Modules

• generators
  Implements various generators.
• structs
  Generator adaptor implementations. See GeneratorExt for more info.
• testtest
  Various test utilities
• traits
  Module containing the various traits used by pushgen.

Enums

• Either
  The enum Either with variants Left and Right is a general purpose sum type with two cases.
• GeneratorResult
  The result of generator runs.
• TryReduction
  The result value of a try_* reduction.
• ValueResult
  Value-consumption result.