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While the article is very entertaining, I'm not a fan of the pattern matching in Python. I wish for some linter rule that can forbid the usage of pattern matchi

While the article is very entertaining, I'm not a fan of the pattern matching in Python. I wish for some linter rule that can forbid the usage of pattern matching.

siddboots 1y ago
Can you explain why? Genuinely curious as a lover of case/match. My only complaint is that it is not general enough.
- kurtis_reed 1y ago
  Double indentation
  - maleldil 1y ago
    So? Other languages with pattern match similarly have such double indentation. C-style switch with unintended cases is weird.
smcl 1y ago
If you're experienced enough with Python to say "I want to eliminate pattern matching from my codebase" you can surely construct that as a pre-commit check, no?
jbmchuck 1y ago
Should be easily doable with a semgrep rule, e.g.: ~> cat semgrep.yaml rules: - id: no-pattern-matching pattern: | match ...: message: | I'm not a fan of the pattern matching in Python severity: ERROR languages: - python ... ~> cat test.py #!/usr/bin/env python3 foo = 1 match foo: case 1: print("one") ... ~> semgrep --config semgrep.yaml test.py no-pattern-matching I'm not a fan of the pattern matching in Python 4┆ match foo: 5┆ case 1: 6┆ print("one") (exits non-0)
- PokestarFan 1y ago
  You need to make that exclude match = ... since match can also be a variable name. This is because people used to write code like match = re.search(...)
  - TheDong 1y ago
    The existing pattern suggested above, "match ...:", will not match 'match = ...'. Presumably the reason the parent comment suggested semgrep, not just a grep, is because they're aware that naive substring matching would be wrong. You could use the playground to check your understanding before implying someone is an idiot. https://semgrep.dev/playground/new https://semgrep.dev/playground/new

While the article is very entertaining, I'm not a fan of the pattern matching in Python. I wish for some linter rule that can forbid the usage of pattern matching.

siddboots 1y ago

Can you explain why? Genuinely curious as a lover of case/match. My only complaint is that it is not general enough.

kurtis_reed 1y ago
Double indentation
- maleldil 1y ago
  So? Other languages with pattern match similarly have such double indentation. C-style switch with unintended cases is weird.

smcl 1y ago

If you're experienced enough with Python to say "I want to eliminate pattern matching from my codebase" you can surely construct that as a pre-commit check, no?

jbmchuck 1y ago

Should be easily doable with a semgrep rule, e.g.: ~> cat semgrep.yaml rules: - id: no-pattern-matching pattern: | match ...: message: | I'm not a fan of the pattern matching in Python severity: ERROR languages: - python ... ~> cat test.py #!/usr/bin/env python3 foo = 1 match foo: case 1: print("one") ... ~> semgrep --config semgrep.yaml test.py no-pattern-matching I'm not a fan of the pattern matching in Python 4┆ match foo: 5┆ case 1: 6┆ print("one") (exits non-0)

PokestarFan 1y ago
You need to make that exclude match = ... since match can also be a variable name. This is because people used to write code like match = re.search(...)
- TheDong 1y ago
  The existing pattern suggested above, "match ...:", will not match 'match = ...'. Presumably the reason the parent comment suggested semgrep, not just a grep, is because they're aware that naive substring matching would be wrong. You could use the playground to check your understanding before implying someone is an idiot. https://semgrep.dev/playground/new https://semgrep.dev/playground/new