GOTO Chaos: Spaghetti Code

This article is dedicated to the late Thomas E. Kurtz, one of BASIC's creators, as it was the first programming language I learned.

TL;DR: GOTO statements create confusing and unmaintainable code

Problems

• Logic becomes unclear
• Debugging gets harder
• Flow jumps erratically
• Code lacks structure
• Maintenance becomes difficult

Solutions

1. Use structured programming
2. Replace with loops
3. Simplify control flow
4. Avoid unnecessary jumps

Context

Spaghetti describes code that is poorly structured and difficult to understand. It often involves deeply nested loops, excessive use of goto statements, and complex control flow.

When you overuse GOTO statements, your program becomes a tangled mess of uncontrolled jumps.

This was common in the 70s when BASIC encouraged GOTO for flow control. While it can solve simple problems quickly, GOTO leads to spaghetti code that’s nearly impossible to debug or extend.

Spaghetti Code << Structured Programming << Object-Oriented Programming << Machine Learning Programming

Sample Code

Wrong

0 REM Request a Zero
10 INPUT "Enter a number: ", N
20 IF N = 0 THEN GOTO 50
30 PRINT "Number is non-zero"
40 GOTO 10
50 PRINT "Goodbye"
60 END

Right

10 DO
20   INPUT "Enter a number: ", N
30   IF N <> 0 THEN PRINT "Number is non-zero"
40 LOOP UNTIL N = 0
50 PRINT "Goodbye"
60 END

Detection

[X] Automatic

You can detect this smell by scanning for frequent GOTO usage, especially when they jump between unrelated code sections.

Look for logical breaks caused by excessive jumping and ask if structured control flow can replace them.

Tags

• Coupling

Level

[X] Beginner

AI Generation

AI generators can include GOTO when mimicking older coding styles.

They might use it for simplicity without considering modern best practices.

AI Detection

You can instruct AI to replace GOTO with loops or structured constructs like IF-ELSE or WHILE.

Try Them!

Remember: AI Assistants make lots of mistakes

Conclusion

Overusing GOTO creates chaotic and unmanageable code.

Replace it with structured programming techniques to improve readability and maintainability.

Relations

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More Info

Wikipedia

Disclaimer

Code Smells are my opinion.

Credits

Photo by Sofia Ciravegna on Unsplash

Spaghetti code is a program with its logic tangled like spaghetti. Avoid the tangles, and you simplify your life.

Martin Fowler

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Maxi Contieri ・ Dec 28 '20

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This article is part of the CodeSmell Series.

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