Thanks JavaFan and LanX.
Points on compile-time and run-time difference are well taken.
BTW, in my original code, I do use strict/warning, and knew that separating the declaration and condition statement makes it work as expected. But still knowing a little more about what is going on under the hood is more satisfactory.

In reply to Re^2: A curious case of of my() by fleetingflicker
in thread A curious case of of my() by fleetingflicker

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