Process code written in textarea?

Question

Windows

The idea is this. The form has a <textarea id="code"></textarea>, in which I write the code.
Let's say:
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var t=5, z=6, m;
m=t+z;
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Next, we have the following component: <div id="result"></div>, where I would like to output the result ... But how to do it I don't really know... Any advice?
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Here's what else is important, I would like to solve the problem using only the possibilities of JavaScript, without PHP or any Frameworks ....
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Thank you!

Answer 1

eval eval('code here') is a help to you - it will be executed as
code . read text from textarea into variable, into eval and result into div

Answer 2

Try adding a script element to the page and write the entire text content of the text area to the innerHTML of that element.