I have noticed that there seems to be no Snap! equivalent of Javascript (and presumably many other languages)'s this variable, that is used to reference the parent array that a child item is in. This makes it difficult or neigh impossible to do something such as storing a script in a list that, when called, modifies said list.
As I understand it, JS this isn’t about arrays, but about objects. An array in JS, like a Snap! list, is a collection of independent items. The same item might be a member of several different arrays. It would be a violation of the principle of first class data if a list item were somehow hardwired into a particular list.
As of v10, Snap! lets you use a dictionary, a/k/a an association list, i.e. a list of name-value pairs, as an object. Each name-value pair is a field of the object. The OOP library provides an inheritance mechanism by including a field named … in each object whose value is another object, from which this object inherits fields. (The name is … rather than, say, parent, because there’s no mechanism in Snap! for translating user data, and the teachers who wanted this feature are German. :~) But, since Snap! itself is translated into different (human) languages, you can say
to get the object’s parent, i.e., its … field.
If you’re using lists as objects in this way, then it does make sense to want a handle on “this object” and indeed Snap! lets you do so, by using… this!
This is perfect, thank you!
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