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Are there any support for first-class patterns in Erlang?
f(SomeMagicPattern) ->
receive
SomeMagicPattern -> ok
end.
If the answer is no (support), do you know any other approach for achieving this? For example, using macros?
No, Erlang doesn’t have first-class patterns out of the box.
There are two ways of implementing this:
Macros. Widely used, for example in testing tools like EUnit and PropEr. Say, EUnit has an ?assertMatch macro, which is in fact an example of first-class patterns:
?assertMatch({ok, _}, Result)
Parse transforms. Harder to write, but potentially more powerful, since using them you can access Erlang abstract code and rewrite it completely, in any way you desire. There’s a nice link to a series of tutorials on parse transforms here: Is there a good, complete tutorial on Erlang parse transforms available?