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Understanding Deferred Array Handling in $.when()
In a scenario similar to the one demonstrated in the provided JSFiddle, an array of deferred tasks is generated and passed to $.when(). However, $.when() by default expects individual deferred objects as arguments and may not handle arrays effectively.
Utilizing Function.prototype.apply
To address this, you can use Function.prototype.apply to pass the array of deferreds as separate parameters. This can be achieved with the following syntax:
$.when.apply($, my_array).then( ___ );
This approach will expand the array into a comma-separated list of individual deferreds, allowing $.when() to process them correctly.
Using ES6 Spread Operator
Alternatively, if you are using ES6 or later, you can employ the spread operator (...) to achieve the same effect more concisely:
$.when(...my_array).then( ___ );
Handling Dynamic Parameter Counts in .then() Handler
Since the number of parameters required by the .then() handler is unknown in advance, it is advisable to process the arguments array to extract the results of each promise. This can be accomplished within the handler function itself.
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