View pattern support right pre-7.10 is fairly limited in that you have to write a chunk of code that can be interpreted as both a pattern and an expression, or limit yourself to just using the syntax for matching.
Afterwards, this opens up a bit, and we get the new syntax for complex bidirectional pattern synonyms, as I recall, so you could make a view pattern for `:<` or something that does this, but we don't have a standard class for it.
-Edward