Argument casting hierarchy?

Meaning I have the following two functions

stats.foo1 (a bigint, b bigint) returns a/b::numeric

stats.foo1 (a real, b real) returns a/b::numeric

It's essentially the same function, but I thought I had to create two to accept the different types.

However, when I call stats.foo1(3::smallint, 4::smallint) I receive the old:

ERROR:  function stats.foo(smallint, smallint) is not unique

Along w/ the message to explicitly cast.

I am essentially trying to write one function that will cast "down", I guess, anything smaller than what's passed. I am guessing I only need the real/real argument signature, but I wanted some clarity from the group.

I appreciate it.

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