I am looking for icons to represent data types in a tree (e.g: string, number, date, array, object etc.). Are there any open source/commercial icon sets for this purpose?
All my Google search keys return generic results.
Good icons should be instantly recognisable - so pitch the problem as, "what will be instantly recognizable as these things?".
This partly depends on the audience - how familiar with the data types are they and how do they normally encounter them? - but it's not going to be a clever visual metaphor or trick, so definitely don't think about balls of string or anything else that requires logical jumps!
Anything other than the simplest example of that data type will require some kind of logical jump (exception: for "date", a very simple calendar icon might be simpler and more robust internationally than a date like
01/02/03). So, that really helpfully narrows your options.
What's the simplest example of each data type? Depends on language, system, etc, and audience, but I'd doubt anything would be more instantly recognisable than (in a container like a circle)
a.b() etc etc.
I think you got generic results because you are requesting icons for things that truly are... generic. Off the top of my head, the only thing that is 100% definitive is a date object, which can be represented by a calendar.
Strings could potentially be represented by an 'abc'. Numbers, contrarily, by '123'. Objects are generic by nature and therefore I do not have suggestions except 'Obj'. Edit: A cube (wireframe) could potentially represent an Object...
While this answer may seem straightforward, I hope you can extract useful information from my 2 cents.