Kernel.is_exception

You're seeing just the macro is_exception, go back to Kernel module for more information.

is_exception(term)

(macro) (since 1.11.0)

Returns true if term is an exception; otherwise returns false.

Allowed in guard tests.

iex> is_exception(%RuntimeError{})
true

iex> is_exception(%{})
false

(macro) (since 1.11.0)

Returns true if term is an exception of name; otherwise returns false.

Allowed in guard tests.

iex> is_exception(%RuntimeError{}, RuntimeError)
true

iex> is_exception(%RuntimeError{}, Macro.Env)
false