I have a pretty easy formula which does not work inside Promise. Problem is following - whatever I put for parameters a and b, I always get failure, even though its clearly more thank 0. I am pretty sure that I am missing something but I can't understand what exactly, because with other formula it works (maybe I cannot call the function inside the Promise? in that case what would be the other way?). Sorry for noob question, Im new to it
const pidr = new Promise((resolve, reject) => {
const result = (a, b) => (a + b) ** 2
result(5, 6)
if (result > 0) {
resolve()
} else {
reject()
}
})
.then(() => console.log('Success'))
.catch(() => console.error('Failure'))
You need to create variable and set result of function execution. See below:
const pidr = new Promise((resolve, reject) => {
const result = (a, b) => (a + b) ** 2
const res = result(5, 6)
if (res > 0) {
resolve()
} else {
reject()
}
})
.then(() => console.log('Success'))
.catch(() => console.error('Failure'))
This:
result(5, 6);
calls the function, but does not save the returned value. You then compare result (which is a function) to 0, and that doesn't make sense.
Instead:
const answer = result(5, 6);
if (answer > 0) {
resolve()
} else {
reject()
}
result is a function and it doesn't have to be, but if you want it to be a function you can call it inside of your if, like so:
const pidr = new Promise((resolve, reject) => {
const result = (a, b) => (a + b) ** 2
if (result(5, 6) > 0) {
resolve()
} else {
reject()
}
})
.then(() => console.log('Success'))
.catch(() => console.error('Failure'))