*Its just spelling*. If it is a useful and well-defined feature, we'll
get used to the spelling soon enough.
That's not to say that spelling is not important *at all*, or that we
should never prefer words to symbols. But if the only objection we have is "this is useful but I don't like the spelling so -1" then that's
usually a pretty weak argument against the feature.
For example, in the following contrived expression the exclamation point !
refers to three distinct functions:
2!!7!4
The function below can be used to list all of the prime numbers between 1 and R with:
2_&{&/x!/:2_!x}'!R