Search key values beginning with number doesn't work

[Ldp]

Create an object, tag it with foo=2bar. Searching for foo=2bar doesn't find any objects. Searching for foo="2bar" works. Why are the quotes a requirement? Am I missing a special search mode where a key value beginning with a number means something special to the search engine?

[mjulius]

This is the way JOSM currently works. If a string starts with a digit the search compiler tries to read a number.

[mjulius]

Closed as duplicate of #4597.

[Ldp]

Fine, but what does the number mean to the search compiler, in this specific case? Is this parsing just a byproduct of the generic parsing for the other search options that have numberic modifiers, like nodes: and timestamp: ?