Capturing true/false

[OvermindDL1]

It would be quite convenient to be able to wrap up true/false into something that returns an exception if on false (maybe if on true via configurable option) or else passes the input value unaltered. An example:

# Assuming test_bool is a something like `safe` is in usage:
request_ip
|> get_client_ip(params)
|> Geoip.lookup_ip() |> normalize # normalize takes a tagged-tuple and converts it to an ErlangError or unwraps an :ok tuple
~> bool_test(should_search?/1).(parse_exclusion_zone(params)) # Here
~> build_search_query(%SearchQuery{}, params)
~> NGSearch.search() |> normalize
~> Analytics.track(client_ip, "api", "search_results")
~> (&json(conn, &1)).()
|> ensure!

Although with macro work could clean it up (and could clean up others, like safe as well).

Basically just return an ErlangError (preferably saying what failed, by saying the passed in 'should_search?/1' failed its test), else it returns the prior passed in value.

[expede]

What sort of exception would the boolean turn into? A few people have asked for automatic conversion in different forms, but there's always information loss versus using a case statement. I think that automation would be amazing if we can do it while preserving context & semantics. I'd love to hear your thoughts!

[OvermindDL1]

What sort of exception would the boolean turn into? A few people have asked for automatic conversion in different forms, but there's always information loss versus using a case statement. I think that automation would be amazing if we can do it while preserving context & semantics. I'd love to hear your thoughts!

Could take that as an argument as well perhaps, maybe defaulting to one of the generic Elixir exceptions?

[OvermindDL1]

This is solved by #18 basically, just without the piping part. ^.^

Close-worthy now or leave open for more thoughts?