is-checks

This is just a POC and has NO real thoughts behind it.

This is basiaclly eventual-values with some extra methods that I wanted.

See:

• eventual-values

example

if ( isError(state) ) {
  return <Error message={ state } />
}
else if ( isPending(state) ) {
  return <Spinner />
}
else if ( isData(state) ) {
  return !isEmpty(state) ? state.map(item => <Item />) : <div>No items to display</div> : 
}

values

| val | isOk(val) | isData(val) | isEmpty(val) | isPending(val) | isError(val) | | ------------------------------------- | --------- | :---------- | ------------ | -------------- | ------------ | | undefined | false | false | true | true | false | | null | true | false | true | false | false | | 1 (number) | true | true | false | false | false | | '' (empty string) | true | true | true | false | false | | 'name' (string) | true | true | false | false | false | | [] or {} | true | true | true | false | false | | [1] or { value: true } | true | true | false | false | false | | throw Error() or Promise.reject() | false | false | true | false | true |