Erlang basics – syntax and assignment of variables

Erlang’s variables are “single assignment”, that is, they cannot be assigned again during the lifetime without being assigned.

Syntax: The first letter must be capitalized (the lowercase begins with an atom) or the underscore begins with the second letter capitalized, such as:

Name

Z

_SomeThing

_Xy

Declaration and assignment:

8> {A, B, C} = {1970, "Richard", male}.
{1970, "Richard", male}
9> A.
1970
10> B.
"Richard"
11> C.
Male
12> 

12> {point, X, Y} = {point, 1, 2}.
{point,1,2}
13> X.
1
14> Y.
2
15> 

Note the following situation: the same variable can appear multiple times in the same pattern, but the two values ​​must be equal:

18> {point, X, X} = {point, 2, 2}.
{point,2,2}
19> X.
2
20>