Code Smell 218 - Magic Concatenation

If you miss a comma, you are concatenating

TL;DR: Watch out for fancy language assumptions

Problems

Solutions

  1. Be declarative

  2. Use good linters

  3. Prefer declarative languages

Context

Many programming languages favor laziness over readability and clean code.

You should use them with caution and trust your tests.

Sample Code

Wrong

tools = [
    "Amazon Codewhisperer",
    "Bard" # Notice the missing comma
    "ChatGPT",
    "Dalle-E" # Also here
    "Eliza"
    ]

print(len(tools))
# This will output 3 

print(tools)
# ['Amazon Codewhisperer', 'BardChatGPT', 'Dalle-EEliza']
# Missing Commas act as hidden string concatenators

Right

tools = [
    "Amazon Codewhisperer",
    "Bard",
    "ChatGPT",
    "Dalle-E",
    "Eliza"
]

# We added all the missing commas

print(len(tools))
# 5

print(tools)
# ['Amazon Codewhisperer', 'Bard', 'ChatGPT', 'Dalle-E', 'Eliza']

Detection

[X] Semi-Automatic

Many linters warn about this problem. Also, ChatGPT and Bard can detect the problem.

Tags

  • Readability

Conclusion

Many modern programming languages come with a significant amount of accidental complexity.

They are often optimized for writing code quickly, even though they may be prone to defects.

Unfortunately, when working with these languages, it is essential to exercise extreme caution.

Relations

Disclaimer

Code Smells are my opinion.

Credits

Photo by Edge2Edge Media on Unsplash


A programming language is low level when its programs require attention to the irrelevant.

Alan J. Perlis


This article is part of the CodeSmell Series.


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