is_prime_number 0.1.0

Prime numbers for Dart: a primality test that stays exact at 64 bits, a sieve, factorisation, and a lazy stream of primes. Pure Dart, no dependencies.

0.1.0

A real package rather than a single function.

Fixed

• isPrime bounded the loop with sqrt(n).toInt(). sqrt returns a double, and one landing a hair under a perfect square truncated low — dropping the final divisor and reporting a composite as prime. The bound is now i * i <= n, entirely in integers.
• Large numbers were tested by trial division alone, which is unusable long before int runs out. Above 50,000 the test is now Miller–Rabin with a witness set proven deterministic across the whole int range.
• The test file was the untouched flutter create template and did not compile — it referenced a Calculator class that never existed. There are now 24 tests.
• The README documented isPrimeNumber(...); the function is isPrime(...).

Changed

• Now a pure Dart package. It never used Flutter, and dropping the SDK dependency lets it run on the server, the web and the command line.

Added

• nextPrime, previousPrime, nthPrime
• primesUpTo, primeCountUpTo — sieve of Eratosthenes over odds only
• primes() — a lazy, infinite iterable
• primeFactors, factorise, divisors
• isPerfect, areTwinPrimes, isCoprime, gcd
• An example, and documentation comments throughout

0.0.1

• isPrime.