I'm trying to learn some programming languages by my own to write the scripts I want to use in my websites, unfortunaly some of stuff I have written doesn't work. And I don't know what I didn't do correctly, so I would like to know if there is any tool that checks code or detect errors in a fragment of code. Any idea?

Depends on the language you are using.

Compiled languages (.net) for example can check at compile time.

Interpreted languages PHP, VbScript, javascript etc can usually only be tested at runtime. So you have to make your own debugging tools and methods.

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And how can we win, when fools can be kings

"most beginners write random codes thinking it would work the way the wanted"
--- anonymous

what language you are using? Incase you are learning a new language, depend on your knowledge and skills instead of some tool or device. That would give more opportunity to learn and explore.

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