node.js - Delay() in the q module -

i using nodejs , learning promises using q module.

i'm misunderstanding delay() fn in q module, think .

when run code:

chain   .then (function() {console.log('starting');})   .then (function() {console.log('waiting 2500ms');})   .delay(2500)   .then (function() {console.log('done');})   .then (function() {console.log('waiting 5500ms');})   .delay(5500)   .then (function() {console.log('done');})   .then(function() {console.log('waiting 4500ms');})   .delay(4500)   .then (function() {console.log('done');})   .then(function() { process.exit(0);}); 

i expect see delays of indicated times.
first delay seems occur.
second delay doesn't seem 5500ms.
third delay, expected 4500ms, doesn't seem happen @ all.

i understanding "delay(x)" mean "then, delay x milliseconds". incorrect? misunderstanding?

if modify code replace each delay(x)

   .then(function() {sleep.usleep(x * 1000);}) 

...then works expect.

can please explain? thanks.

the delay() little different else expect, makes uglier chain them. learned discussion here.

q()   .then (function() {console.log('starting');})   .then (function() {console.log('waiting 2500ms');})   //.delay(2500)   .then( function () { return q().delay( 2500 ); } )   .then (function() {console.log('done');})   .then (function() {console.log('waiting 5500ms');})   //.delay(5500)   .then( function () { return q().delay( 5500 ); } )   .then (function() {console.log('done');})   .then(function() {console.log('waiting 4500ms');})   //.delay(4500)   .then( function () { return q().delay( 4500 ); } )   .then (function() {console.log('done');})   .then(function() { process.exit(0);}); 

hopefully fix soon.