ethereum-types refactor

Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+description = "Large fixed-size integers arithmetics"
+homepage = "http://parity.io"
+repository = "https://github.com/ethcore/bigint"
+license = "MIT/Apache-2.0"
+name = "uint"
+version = "0.1.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+build = "build.rs"
+
+[build-dependencies]
+rustc_version = "0.2"
+
+[dependencies]
+rustc-hex = { version = "1.0", optional = true }
+heapsize = { version = "0.4", optional = true }
+byteorder = { version = "1", default-features = false }
+
+[dev-dependencies]
+quickcheck = "0.4"
+
+[features]
+heapsizeof = ["heapsize", "std"]
+std = ["rustc-hex"]
+
+[[example]]
+name = "modular"
+required-features = ["std"]

build.rs

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+// Copyright 2015-2017 Parity Technologies
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+extern crate rustc_version;
+
+use rustc_version::{version_meta, Channel};
+
+fn main() {
+	if let Channel::Nightly = version_meta().unwrap().channel {
+		println!("cargo:rustc-cfg=asm_available");
+	}
+}

examples/modular.rs

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+// Copyright 2015-2017 Parity Technologies
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+extern crate uint;
+
+use uint::U256;
+
+fn main() {
+	// Example modular arithmetic using bigint U256 primitives
+
+	// imagine the field 0..p
+	// where the p is defined below
+	// (it's a prime!)
+	let p = U256::from_dec_str(
+		"38873241744847760218045702002058062581688990428170398542849190507947196700873"
+	).expect("p to be a good number in the example");
+
+	// then, on this field,
+	// (p-1) + (p+1) = 0
+
+	// (p - 1) mod p
+	let p_minus_1 = (p - 1u64.into()) % p;
+	// (p + 1) mod p
+	let p_plus_1 = (p + 1u64.into()) % p;
+	// ((p - 1) mod p + (p + 1) mod p) mod p
+	let sum = (p_minus_1 + p_plus_1) % p;
+	assert_eq!(sum, 0.into());
+
+	// on this field,
+	// (p-1) + (p-1) = p-2
+	let p_minus_1 = (p - 1u64.into()) % p;
+	let sum = (p_minus_1 + p_minus_1) % p;
+	assert_eq!(sum, p - 2.into());
+
+	// on this field,
+	// (p-1) * 3 = p-3
+	let p_minus_1 = (p - 1u64.into()) % p;
+
+	// multiplication is a series of additions
+	let multiplicator = 3;
+	let mul = {
+		let mut result = p_minus_1;
+		for _ in 0..multiplicator-1 { 
+			result = (p_minus_1 + result) % p;
+		}
+		result
+	};
+
+	assert_eq!(mul, p - 3.into());
+}

src/lib.rs

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+// Copyright 2015-2017 Parity Technologies
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Efficient large, fixed-size big integers and hashes.
+
+#![cfg_attr(asm_available, feature(asm))]
+
+#[doc(hidden)]
+pub extern crate byteorder;
+
+#[cfg(feature="heapsizeof")]
+#[doc(hidden)]
+pub extern crate heapsize;
+
+#[cfg(feature="std")]
+#[doc(hidden)]
+pub extern crate core;
+
+#[cfg(feature = "std")]
+#[doc(hidden)]
+pub extern crate rustc_hex;
+
+mod uint;
+pub use uint::*;