# Simple variable interation

**URL:** <https://community.thunkable.com/t/simple-variable-interation/3003458>\
**Category:** Questions about Thunkable X\
**Tags:** beginner\
**Created:** [May 14, 2024, 7:27pm UTC](https://community.thunkable.com/t/simple-variable-interation/3003458 "2024-05-14T19:27:39Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![tatiang](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/tatiang/32/55482_2.png) [@tatiang](https://community.thunkable.com/u/tatiang)\
**Post date:** [May 14, 2024, 8:26pm UTC](https://community.thunkable.com/t/simple-variable-interation/3003458/2 "2024-05-14T20:26:55Z")

</div>

Here’s the problem… you have to think of every block as a function. Each block is in essence returning a value. So when you do this:

 ![image](https://us1.discourse-cdn.com/flex015/uploads/thunkable/original/3X/5/1/512ba58e9308d694520c53eb840baf9446c1777c.png)

Then Thunkable compiles those blocks by first getting the value of `app variable 1st counter` (let’s say it’s 0) and then looking for an app variable with that name (in this case, `app variable 0`) but it doesn’t exists so it fails.

When you change an app variable, use the `change app variable 1st counter` block at the **top** of the Variables drawer rather than the dynamic block at the bottom that requires a variable name.

> [@jmpalcs7pkl](#):
>
> Separate question. Is there a code watch window so we can see how variable change throughout the flow? I guess a debugging window would kinda defeat the concept of a code free build.

No. This is sorely needed and has been requested before.

I use a workaround method for stepping through the code and debugging a project. The link is below.

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Need help? [How to Ask Great Questions](https://community.thunkable.com/t/how-to-ask-great-questions-v2-0/2689983) ✨ [Debugging A Project](https://community.thunkable.com/t/debugging-in-thunkable-x-video/849471) ✨ [API JSON Tutorial](https://community.thunkable.com/t/api-json-tutorial-video/1140575)

Want to hire a Certified Thunkable Expert? [Elevate your app with Tatiang on Fiverr](https://www.fiverr.com/s/726B4a)

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