safe-bigmath

Safe, non-panicking numeric primitives built on pure-Rust num-bigint. safe-bigmath gives you:

• SafeInt: arbitrary-precision integers with ergonomic operator overloads.
• SafeDec<D>: fixed-scale decimals backed by arbitrary-precision SafeInt; the const generic D sets how many decimal places are stored exactly.
• Parsing helpers for turning strings into safe numeric values.
• No hidden panics: division returns Option, parsing reports structured errors.
• std by default; disable default features for no_std + alloc (works on wasm32-unknown-unknown).

Quick start

[dependencies]
safe-bigmath = "0.2"

# Optional: go `no_std` + `alloc`
# safe-bigmath = { version = "0.2", default-features = false }

Safe integers

use safe_bigmath::SafeInt;

let a = SafeInt::from(10);
let b = SafeInt::from(3);

assert_eq!((&a / &b).unwrap(), SafeInt::from(3)); // division is fallible
assert_eq!(&a + &b, SafeInt::from(13));
assert_eq!(SafeInt::from(5) / SafeInt::from(0), None); // no panic on zero div

Fixed-scale decimals

use safe_bigmath::SafeDec;

let price: SafeDec<2> = "12.50".parse().unwrap();
let qty: SafeDec<2> = "3.00".parse().unwrap();
let total = price * qty;

assert_eq!(total.to_string(), "37.50");

Pow of ratios with scaling

Compute (x / (x + dx))^(w1 / w2) scaled to perquintill:

use safe_bigmath::SafeInt;

let x = SafeInt::from(21_000_000_000_000_000u64);
let dx = SafeInt::from(7_000_000_000_000_000u64);
let w1 = SafeInt::from(600_000_000_000_000_000u128);
let w2 = SafeInt::from(400_000_000_000_000_000u128);
let perquintill = SafeInt::from(1_000_000_000_000_000_000u128);

let result = SafeInt::pow_ratio_scaled(&x, &(x.clone() + dx), &w1, &w2, 0, &perquintill).unwrap();
assert_eq!(result, SafeInt::from(649_519_052_838_328_985u128));

Feature flags

• std (on by default): enables std support for downstream crates; disable default features for no_std + alloc.

Supported targets

• std targets (default).
• no_std targets with alloc via --no-default-features.
• wasm32-unknown-unknown (CI builds and test-compiles both --no-default-features and --all-features).

Testing

cargo test --workspace
cargo test --workspace --no-default-features
cargo test --workspace --all-features
cargo test --target wasm32-unknown-unknown --no-default-features --no-run
cargo test --target wasm32-unknown-unknown --all-features --no-run

License

MIT © sam0x17