Repetition among matches

[yfaria]

Sometimes, the matches "collide" with themselves, which is not necessarily a problem but in the interface it may be confusing.
For example, when I run the query

h1:[rstr h2] 
h3:[]

It's possible that h1 matches with the same predication as h3. When it doesn't it, it is displayed as expected:

When it collides, one example is like that:

Maybe there should be a color change when there is more than one match in a predicate.

[arademaker]

We may need to expose the project to DELPH-IN members to have feedbacks. See delph-in/docs#24

In the meantime, I believe we have two questions here:

1. do we want that h3: [] denote any predication? Because h:[* x] is a predication with hole h with an argument with x as value... so if we omit the pattern inside the brackets we are saying anything? So what is the denotation of the empty string as a query?

2. different variables may have the same bind or not? If I have h1 and h2, do we adopt the standard FOL semantics where they can both point to the same individual or we adopt a more practical approach were different variables should not have the same bind... what is the SPARQL semantics for that? I need to double-check.