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In this sentence! What does it mean?
+Can turn back into numbers (Number type).
!Is to reverse the boolean type.
Specifically, we need to see what we are doing.
I don’t know why I want to change so much.
!+'test'// true !'test' // false !+'0' //true !'0' // false
+Is to let strings become numeric types.
！It is the opposite.
Look at specific fields for understanding.
Here it should be to determine if a value is 0.