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Having + for list concatenation

This code insight counts one violation each time a "+" operator is involved in list concatenation.

Why you should care

Extending a list through a reassignment is not recommended since Python offers other solution for that task with significant performance benefits.

Business Impacts

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CAST recommendations

References

https://www.quantifiedcode.com/knowledge-base/performance/Use%20%60extend%28%29%60%20for%20list%20concatenation/3kr7yXet

About CAST and Highlight’s Code Insights

Over the last 25 years, CAST has leveraged unique knowledge on software quality measurement by analyzing thousands of applications and billions of lines of code. Based on this experience and community standards on programming best practices, Highlight implements hundreds of code insights across 15+ technologies to calculate health factors of a software.

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For reference only. For the complete details please refer the original article
https://doc.casthighlight.com/alt_unnecessaryconcat-avoid-for-list-concatenation/