i want to add a condition in the add_entry to limit the input such like if else in java, any help server.ex def add_entry(todo_server, new_entry) do GenServer.cast(todo_server, {:add_entry, new_entry}) end @impl GenServer def handle_cast({:add_entry, new_entry}, {name, todo_list}) do …

If your map contains keys like :date, :time, etc., then your code above won’t work (because it matches an entry with key :entries). There are a few possible ways to solve this. First, you could check if any of the entry fields is blank. Remember that maps are Enumerable, so you can enumerate them a…

Todo.Server.add_entry(test, %{date: ~D[2020-05-19], time: ~T[16:52:00], title: "Shopping"}) this is what the input and I want to set it if any of the value is nil or empty it return an IO statement " input cannot be empty and return to the same iex

[image] mindok: %{thing: thing}=ent so follow the idea you gave is it like this? def add_entry(todo_list, %{entries: entries}=entry) when entries ==" ", do: IO.puts("input cannot be empty!") end def add_entry(todo_list, %{}=entry) do entry = Map.put(entry, :id, todo_list.auto_id) …

Close… def add_entry(todo_list, %{entries: entries}=entry) when entries =="", do: todo_list or… def add_entry(todo_list, %{entries: entries}=entry) when entries ==" " do IO.puts("input cannot be empty!") todo_list # Return the unaltered input so the calling code is consistent end

But the question here is: do you want to raise an exception, or return an erroneous value to the caller? If exception is fine, you can just pattern match the happy path like this: def add_entry(list, %{entries: text}) when text != "" do # do stuff with valid input end Then, if the function is ca…

what if I want to return an erroneous value?is that I need to set up an error statement by myself?

Show us what you have tried to make the function return an error value?

so if i not enter both value there will having a crash appear [image] so i want to make it limited at the input part to stop this happening

[image] dimitarvp: mix new … i have no idea :sweat_smile: my teacher just give a base code like this one and ask us to make it efficiency/ capacity and fault tolerance, that why i have the idea to make it unable put empty and werid value at the beginning.

def add_entry(_server, _entry), do: {:error, "Invalid input"} end what is this line is about? before that three i have some idea what they are doing but this line seems like is doesn’t do anything?

Elixir Programming Language Forum

How to put a if else in a function

Questions & Help Questions

dimitarvp May 22, 2020, 9:46am 13

Why is your repo not a normal Mix project, created with mix new ...?