Function arbitrary

pub fn arbitrary<A, S>() -> S
where
    S: Strategy<Value = A>,
    A: Arbitrary<Strategy = S>,

Generates a Strategy producing Arbitrary values of A. Works better with type inference than any::<A>().

With this version, you shouldn’t need to specify any of the (many) type parameters explicitly. This can have a positive effect on type inference. However, if you want specify A, you should use any::<A>() instead.

For clarity, it is often a good idea to specify the type generated, and so using any::<A>() can be a good idea.

If you want to customize how the strategy is generated, use arbitrary_with(args) where args is of type <A as Arbitrary>::Parameters.

Example

The function can be used as:

extern crate proptest;
use proptest::arbitrary::{arbitrary, StrategyFor};

fn gen_vec_usize() -> StrategyFor<Vec<usize>> {
    arbitrary()
}