This error indicates that a program uses an invalid assignment operator.
Reach only supports assignment using the
= operator. Any other operator,
+=, *=, ... is not allowed.
For example, the code below erroneously tries to re-assign
x at the end of
x *= 2; continue;
You can fix this by explicitly writing out the operation on the right hand
Keep in mind, that the assignment operator is a form of mutation and is only allowed
immediately before a