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Rosetta Code Sieve of Eratosthenes Example

[The following task description was taken from rosettacode.org:]

Implement the Sieve of Eratosthenes algorithm, with the only allowed optimization that the outer loop can stop at the square root of the limit, and the inner loop may start at the square of the prime just found.

That means especially that you shouldn't optimize by using pre-computed wheels, i.e. don't assume you need only to cross out odd numbers (wheel based on 2), numbers equal to 1 or 5 modulo 6 (wheel based on 2 and 3), or similar wheels based on low primes.

If there's an easy way to add such a wheel based optimization, implement it as an alternative version.

Using Loops

Using Sequences

Using Sequences and Filters

Using Pipes

Infix operators are provided as aliases for some operations on Sequences such that elements could be piped. Examples are these operations:

infix operation	is alias for
`a \| (x -> f x)`	`a.map (x -> f x)`
`a & (x -> f x)`	`a.filter (x -> f x)`
`a ! (x -> f x)`	`a.for_each (x -> f x)`

Using these operations results in a pipe-style code as follows:

Purely functional implementation using ps_set

ps_set is a persistent set data structure in Fuzion's standard library with well-behaved cumulative and average performance:

Purely functional implementation using bitsets

bitset is a persistent data structure in Fuzion's standard library that (currently) does not have good cumulative or average performance:

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