Value and Error Sequences

If any step of a sequence is just a normal value, that value is just mapped to that step’s completion message:

var sq = ASQ( 42 );
sq.val( function(msg){
    console.log( msg );        // 42
} );

If you want to make a sequence that’s automatically errored:

var sq = ASQ.failed( "Oops" );
ASQ()
.seq( sq )
.val( function(msg){
    // won't get here
} )
.or( function(err){
    console.log( err );        // Oops
} );

You also may want to automatically create a delayed-value or a delayed-error sequence. Using the after and failAfter contrib plug-ins, this is easy:

var sq1 = ASQ.after( 100, "Hello", "World" );
var sq2 = ASQ.failAfter( 100, "Oops" );
sq1.val( function(msg1,msg2){
    console.log( msg1, msg2 );        // Hello World
} );
sq2.or( function(err){
    console.log( err );                // Oops
} );

You can also insert a delay in the middle of a sequence using after(..):

ASQ( 42 )
// insert a delay into the sequence
.after( 100 )
.val( function(msg){
    console.log( msg );        // 42
} );