注意数值型的字面值不包括符号(译注：正负号)，像- 1实际上是个组合了一元运算符“-”和字面值1的表达式。

Note that numeric literals do not include a sign; a phrase like -1 is actually an expression composed of the operator - and the literal 1.

youdao

注意数值型的字面值不包括符号(译注：正负号)，像- 1实际上是个组合了一元运算符“-”和字面值1的表达式。

Note that numeric literals do not include a sign; a phrase like -1 is actually an expression composed of the unary operator '-' and the literal 1.

youdao