Ahti Kitsik
Building develper tools. Python, Java, JavaScript.

writings about @ahtik

Lazy-init variables are not always safe

By Ahti Kitsik, 16 May 2006

Have you ever used following to lazy-initialize your variable?

If you have then don't.

Just to remind or introduce, it looks OK but it isn't - this is a pretty serious bug you can easily make.

And it's called Double-Checked Locking.
Very good and easy-to-understand explanation is here

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