2025-06-16 18:28:08 +05:00

43 lines
1.4 KiB
JavaScript
Executable File

// Full credit goes to: https://github.com/purplestone/exhaust
// However, it is modified so that it is a bit more modern
export function produce(blueprint) {
let groups = []
// Call the blueprint once so that we can collect all the possible values we
// spit out in the callback function.
blueprint((...args) => {
if (args.length <= 0) throw new Error('Blueprint callback must have at least a single value')
groups.push(args)
})
// Calculate how many combinations there are
let iterations = groups.reduce((total, current) => total * current.length, 1)
// Calculate all the combinations possible
let zippedGroups = []
let currentIteration = iterations
groups.forEach((a) => {
let n = a.length
currentIteration = currentIteration / n
let iS = -1
let aS = []
for (let i = 0; i < iterations; i++) {
if (!(i % currentIteration)) iS++
aS.push(a[iS % n])
}
zippedGroups.push(aS)
})
// Transpose the matrix, so that we can get the correct rows/columns structure
// again.
zippedGroups = zippedGroups[0].map((_, i) => zippedGroups.map((o) => o[i]))
// Call the blueprint again, but now give the inner function a single value
// every time so that we can build up the final result with single values.
return zippedGroups.map((group) => {
let i = 0
return blueprint(() => group[i++])
})
}