The Shell
The Erlang shell is where you’ll spend most of your time. You enter an expression, and the shell evaluates the expression and prints the result.
| $ erl |
| Erlang R16B ... |
| Eshell V5.9 (abort with ^G) |
| 1> 123456 * 223344. |
| 27573156864 |
So, what happened? $
is the operating system prompt.
We typed the command erl
, which started the Erlang
shell. The Erlang shell responds with a banner and the numbered
prompt 1>
. Then we typed in an expression,
which was evaluated and printed. Note that each expression
must be finished with a dot followed by a whitespace
character. In this context, whitespace means a space, tab, or
carriage return character.
Beginners often forget to finish expressions with the dot whitespace bit. Think of a command ...
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