catchError

Runs a specific sequence when an error occurs, and prevents the original error message from being emitted

function catchError(second : IObservable.<T>) : IObservable.<T>

Where second is the observable sequence to subscribe to when an error in the source sequence occurs.

Remarks

The returned sequence completes when the source sequence completes.

The returned sequence errors if an error occurs in the second sequence and an error occurs in second.

Marble Diagrams

xs    ──o─────o─────x
        │     │     │
other   │     │     └─o─o─/
        │     │       │ │ │
ys    ──o─────o───────o─o─/

xs    ──o─────o─────x
        │     │     │
other   │     │     └─x
        │     │       │
ys    ──o─────o───────x

xs    ──o─────o─────/
        │     │     │
other   │     │     │
        │     │     │
ys    ──o─────o─────/

Return Value

IObservable.<T>

Examples

Observable.error(new Error())
    .catchError(toObservable([1, 2, 3]))
    .subscribe(
        function(x:int) : void { trace(x); },
        function() : void { trace("Completed"); },
        function(e:Error) : void { trace("Error: " + e.message); }
    );

    // Trace output is:
    // 1
    // 2
    // 3
    // Completed