What's the point of applicative-style generator creation? #13
Description
The README has this example (albeit slightly modified since int_uniform_inclusive doesn't exist anymore):
fn box_generator() {
qcheck.return({
use x <- qcheck.parameter
use y <- qcheck.parameter
use w <- qcheck.parameter
use h <- qcheck.parameter
Box(x:, y:, w:, h:)
})
|> qcheck.apply(qcheck.bounded_int(-100, 100))
|> qcheck.apply(qcheck.bounded_int(-100, 100))
|> qcheck.apply(qcheck.bounded_int(1, 100))
|> qcheck.apply(qcheck.bounded_int(1, 100))
}This can just be written using map+bind (i.e. in a monadic fashion), and it is cleaner and considerably less error-prone:
fn box_generator() {
use x <- qcheck.bind(qcheck.bounded_int(-100, 100))
use y <- qcheck.bind(qcheck.bounded_int(-100, 100))
use w <- qcheck.bind(qcheck.bounded_int(1, 100))
use h <- qcheck.map(qcheck.bounded_int(1, 100))
Box(x:, y:, w:, h:)
}What benefits does the applicative API have? I don't see how composed generators being independent of each other is useful for Generators; is it something to do with shrinking?