Respect the Built-in Names

PyCon JP 2017 Day1 Lightning Talk

Transcript

1. Respect the Built-in Names
   Hayao Suzuki
   PyCon JP 2017 Lightning Talk at Waseda Univ.
   September 8, 2017
   

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2. Who Am I?
   About Me
   Name Hayao Suzuki (@CardinalXaro)
   Blog http://xaro.hatenablog.jp/
   Major Mathematics (Combinatorics, Number Theory)
   Work Python Programmer at iRidge, Inc.
   Reviewed Books
   Effective Python (O’Reilly Japan)
   ΞϧΰϦζϜΫΠοΫϦϑΝϨϯε ୈ 2 ൛ (O’Reilly Japan)
   ॳΊͯͷ PHP (O’Reilly Japan)
   Effective Debugging (O’Reilly Japan)
   ͢Β͢ΒΘ͔Δ Python ʢᠳӭࣾʣ
   Python ͱ JavaScript Ͱ͸͡ΊΔσʔλϏδϡΞϥΠθʔγϣϯ
   (O’Reilly Japan)
   2 / 9
   

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3. Today’s Theme
   Respect the Built-in Names
   3 / 9
   

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4. Examples
   sum is a name of built-in function but...
   sum = 0
   for i in range(10):
   sum = sum + i
   print(sum)
   sum ΁ͷ୅ೖ͸ѱ͍จ໌ʂʂ
   4 / 9
   

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5. Examples
   id is a name of built-in function but...
   id = 12345
   name = "Ξϧςϥ"
   print(f"Α͏ͦ͜{name}͞Μ (id={id})")
   id ΁ͷ୅ೖ͸ѱ͍จ໌ʂʂ
   5 / 9
   

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6. Examples
   list is a name of sequence class but...
   list = [1, 2, 3, 4, 5]
   for i in range(len(list)):
   print(list[i])
   list ΁ͷ୅ೖ͸ѱ͍จ໌ʂʂ
   6 / 9
   

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7. Examples
   dict is a name of mapping class but...
   dict = {"spam": 0, "egg": 1, "bacon":2}
   for k, v in dict.items():
   print("%s: %s" % (k, v))
   dict ΁ͷ୅ೖ͸ѱ͍จ໌ʂʂ
   7 / 9
   

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8. Examples
   json is a name of built-in module but...
   import json
   import requests
   response = requests.get("https://examples.com")
   if response.status_code == 200:
   json = response.json()
   print(json.keys())
   json ΁ͷ୅ೖ͸ѱ͍จ໌ʂʂ
   8 / 9
   

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9. Conclusion
   Respect the built-in names
   Abuse of names causes a trouble.
   If you provide objects with the same name as a built-in
   value, read builtins module’s documents.
   9 / 9
   

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