... The function returned by $Y (the wrapping function) meets the following requirements:
* It always returns an instance of {{jsx3.$AsyncRV}}.
* It can take any of a number of parameters. Consult the API documentation of the function for the expected parameters.
h3. A Simple Example
Any function passed to the {{when()}} method of {{jsx3.$AsyncRV}} is called when the asynchronous method is done.
The function is passed a single parameter, which is the asynchronous return value of the asynchronous function, as in the following example: {code:lang=javascript}var rv = loadXmlAsync("data.xml");
rv.when(function(doc) {
jsx3.log("The asynchronous return value is: " + doc);
});{code}
h3. Multiple Callbacks
A program can call {{when()}} any number of times before or after the asynchronous method finishes. Regardless of when it is called, all callbacks are invoked. For example: {code:lang=javascript}var rv = loadXmlAsync("data.xml");
rv.when(function(doc) {
jsx3.log("Got document: " + doc);
});
rv.when(function(doc) {
doSomethingElse(doc);
});{code}
h3. Condition Chaining
Use the {{and()}} and {{or()}} methods of {{jsx3.$AsyncRV}} to chain asynchronous return conditions. Both methods also return instances of {{jsx3.$AsyncRV}}. For example: {code:lang=javascript}var rv1 = loadXmlAsync("data1.xml");
var rv2 = loadXmlAsync("data2.xml");
rv1.and(rv2).when(function() {
jsx3.log("Got docs: " + rv1.rv() +
" and " + rv2.rv());
});{code}
h3. Automatic Parameter Resolution
If an instance of {{jsx3.$AsyncRV}} is passed as a parameter to an asynchronous function, the function automatically waits for the parameter to be available before calling the wrapped function.
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