How do I convert a float to an integer in Elixir
Use trunc(2.0) or round(2.0). Those are auto-imported since they are part of Kernel and they are also allowed in guard clauses.
elixir
Why can’t I chain String.replace?
EDIT On the master branch of Elixir, the compiler will warn if a function is piped into without parentheses if there are arguments. This is an issue of precedence that can be fixed with explicit brackets: price |> to_string |> String.replace(“.”, “,”) |> String.replace(~r/,(\d)$/, “,\\1 0″) |> String.replace(” “, “”) Because function calls have a … Read more
What does the slash notation in Elixir mean?
From page 2, Basic types of the Getting started documentation: Note: Functions in Elixir are identified by name and by number of arguments (i.e. arity). Therefore, is_boolean/1 identifies a function named is_boolean that takes 1 argument. is_boolean/2 identifies a different (nonexistent) function with the same name but different arity. It is also described in Erlang/Elixir … Read more
How to change field type in Ecto?
You have to use modify/3 to change the type. add/3 is only for adding new columns. alter table(:editables) do modify :content, :binary end
Testing a file upload in phoenix/elixir
Put a file in your test directory somewhere (maybe test/fixtures) then use the Plug.Upload struct: upload = %Plug.Upload{path: “test/fixtures/example.png”, filename: “example.png”} conn() |> post(“/api/v1/originals”, %{ :image => upload })
How do I convert an float to an integer in Elixir
Use trunc(2.0) or round(2.0). Those are auto-imported since they are part of Kernel and they are also allowed in guard clauses.
Is there an identity function in Elixir?
@focused is correct – 1.10-dev has added the identity function. Documentation Old Answer: No such function has been predefined (at least that I’m aware of). It can trivially be written as you’ve done in your question, or more succinctly as &(&1).
Equivalent of IO.inspect function that just returns string instead of printing given list, map or keyword list?
inspect([name: “John Doe”]) It is defined by the Kernel module and therefore automatically imported.
Return statement in Elixir
This is an interesting problem because you need to perform multiple checks, exit early, and in the process transform some state (connection). I typically approach this problem as follows: I implement each check as a function which takes state as an input and returns {:ok, new_state} or {:error, reason}. Then, I build a generic function … Read more
List comprehension with counter in Elixir
Use Enum.with_index: iex(1)> for {value, index} <- Enum.with_index([“a”, “b”]), do: {value, index} [{“a”, 0}, {“b”, 1}]