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Respect the Built-in Names
Hayao Suzuki
PyCon JP 2017 Lightning Talk at Waseda Univ.
September 8, 2017
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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 Ͱ͡ΊΔσʔλϏδϡΞϥΠθʔγϣϯ
(O’Reilly Japan)
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Today’s Theme
Respect the Built-in Names
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Examples
sum is a name of built-in function but...
sum = 0
for i in range(10):
sum = sum + i
print(sum)
sum ͷೖѱ͍จ໌ʂʂ
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Examples
id is a name of built-in function but...
id = 12345
name = "Ξϧςϥ"
print(f"Α͏ͦ͜{name}͞Μ (id={id})")
id ͷೖѱ͍จ໌ʂʂ
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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 ͷೖѱ͍จ໌ʂʂ
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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 ͷೖѱ͍จ໌ʂʂ
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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 ͷೖѱ͍จ໌ʂʂ
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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.
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