An assignmentOpExpression performs an arithmetic operation, then assigns the result to the variable or sequence element referenced on the left-hand-side.
Table 6.2. Assignment Operators
| Operator | Meaning | Operand Types | Result Type |
|---|---|---|---|
| += | Add then assign | Integer += Integer | Integer |
| Integer += Number | Integer | ||
| Number += Integer | Number | ||
| Number += Number | Number | ||
| Duration += Duration | Duration | ||
| -= | Subtract then assign | Integer -= Integer | Integer |
| Integer -= Number | Integer | ||
| Number -= Integer | Number | ||
| Number -= Number | Number | ||
| Duration -= Duration | Duration | ||
| *= | Multiply then assign | Integer *= Integer | Integer |
| Integer *= Number | Integer (computed using Number) | ||
| Number *= Integer | Number | ||
| Number *= Number | Number | ||
| Duration *= Integer | Duration | ||
| Duration *= Number | Duration | ||
| /= | Divide then assign | Integer /= Integer | Integer |
| Integer /= Number | Integer (computed using Number) | ||
| Number /= Integer | Number | ||
| Number /= Number | Number | ||
| Duration /= Integer | Duration | ||
| Duration /= Number | Duration |
Tween expressions are used in animation, see the Animation chapter.