the existing implementation of lambda-case was strangely-limited: only a single pattern-rhs pair was allowed. with this PR, several are now allowed.
I added a new file to test this feature, and in doing so, I found a flaw in my reimplementation of the golden tests accidentally dropped an important feature: generating the golden files when they don't yet exist. this PR fixes that too.
the existing implementation of lambda-case was strangely-limited: only a single pattern-rhs pair was allowed. with this PR, several are now allowed.
I added a new file to test this feature, and in doing so, I found a flaw in my reimplementation of the golden tests accidentally dropped an important feature: generating the golden files when they don't yet exist. this PR fixes that too.