Lazy

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2023-12-01

Wraps an object and returns a Sequence. For null or undefined, simply returns an empty sequence (see Lazy.strict for a stricter implementation).

For arrays, Lazy will create a sequence comprising the elements in the array (an ArrayLikeSequence).
For objects, Lazy will create a sequence of key/value pairs (an ObjectLikeSequence).
For strings, Lazy will create a sequence of characters (a StringLikeSequence).

Signature

function Lazy(source) { /*...*/ }

function Lazy(source) {
  if (isArray(source)) {
return new ArrayWrapper(source);

  } else if (typeof source === "string") {
return new StringWrapper(source);

  } else if (source instanceof Sequence) {
return source;
  }

  if (Lazy.extensions) {
var extensions = Lazy.extensions, length = extensions.length, result;
while (!result && length--) {
  result = extensions[length](source);
}
if (result) {
  return result;
}
  }

  return new ObjectWrapper(source);
}

Name	Type(s)	Description
source	Array\|Object\|string	An array, object, or string to wrap.
returns	Sequence	The wrapped lazy object.

Examples

Lazy([1, 2, 4])       // instanceof Lazy.ArrayLikeSequence
Lazy({ foo: "bar" })  // instanceof Lazy.ObjectLikeSequence
Lazy("hello, world!") // instanceof Lazy.StringLikeSequence
Lazy()                // sequence: []
Lazy(null)            // sequence: []