In Erlang, how do you invoke a function dynamically?

Question

I want to call xyz with the name of a function to be invoked. ``` -module(sample). -export([xyz/1]). xyz(Name) -> Name(). p() -> "you called p". g() -> "you called g". ``` But I get the following error: ``` 1> c(sample.erl). ./sample.erl:6: Warning: function p/0 is unused ./sample.erl:7: Warning: function g/0 is unused {ok,sample} 2> sample:xyz('p'). ** exception error: bad function p in function sample:xyz/1 3> ```

Accepted Answer

It is correct that you have to export p and g. You can then use `apply/3` to call it.

```
erlang:apply(sample, p, []).
```

Only fun-values are usable with the Fun(...) syntax. You are passing in an atom-value. An atom is a 'bad function' as the error message go. You could do something similar to

```
xyz(p) -> fun p/0;
xyz(g) -> fun g/0.
```

Then go ahead and call

```
Fun = xyz(p),
Fun()
```

In Erlang, how do you invoke a function dynamically?

Solution

Problem