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isUninitialized()

Call this inside a computed signal function to determine whether it is the first time the function is being called.

Mainly useful for incremental signal computation.

Example​

const count = atom('count', 0)
const double = computed('double', (prevValue) => {
  if (isUninitialized(prevValue)) {
    console.log('First time!')
  }
  return count.value * 2
})

@param value - The value to check.
@public

## Signature

```ts
isUninitialized(value: any): value is typeof UNINITIALIZED;

Parameters​

NameType
valueany

Returns​

value is typeof UNINITIALIZED

Defined in: signia/src/Computed.ts:39