TS1107

Jumping out of a callback

Jump target cannot cross function boundary.

The compiler’s own words. Not translated — this is the string you pasted into a search box.

`break` and `continue` steer the loop they are written in. A callback is a different function, and that loop is not its to steer.

Reproduction

const ids = [1, 2, 3]
const kept: number[] = []

for (const id of ids) {
  ids.forEach(() => {
    if (id > 2) continue
  })
  kept.push(id)
}

The build asserts this emits exactly this code.

Why the compiler says this

`forEach` takes a function, and that function is called by `forEach` rather than by the loop. `continue` names a jump to the next iteration of an enclosing loop, and from inside the callback nothing encloses it but a call. The compiler rejects this while parsing, before it knows any types at all, because no arrangement of types would make the jump meaningful.

Fixes

const ids = [1, 2, 3]
const kept: number[] = []

for (const id of ids) {
  if (id > 2) continue
  kept.push(id)
}

Use a real loop. `for…of` gives `continue` something to jump to, and reads as the iteration it already was.

02
```
const ids = [1, 2, 3]
const kept = ids.filter((id) => id <= 2)
```
Or stop steering and describe the result. Most `continue` inside a callback is a filter that has not been written as one.

Takeaway

Inside a callback the only way out is `return`. If you meant to skip or to stop, the array method that means "skip" or "stop" is usually the real answer.

Errors