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From what I gather from that article is that pattern matching is the new buzzword for Switch Cases? If so, expect an influx of applications misusing switches i

From what I gather from that article is that pattern matching is the new buzzword for Switch Cases? If so, expect an influx of applications misusing switches in replacement of if.

cassianoleal 6y ago
It's certainly not, although it can be used in switch cases. Pattern matching is a great language feature but I've been watching the development of it for Python for a while and have felt nothing but horror. If you want a great example of how it can be useful and how clear and elegant it can be, check out how it's done in Elixir [0]. There are many other languages that implement it in great ways, I'm sure others will comment on them. [0] https://elixir-lang.org/getting-started/pattern-matching.html https://elixir-lang.org/getting-started/pattern-matching.htm...
- sammorrowdrums 6y ago
  Yes,oddly I love it I Rust, it is probably a favourite feature, but I am not really excited about it in Python. https://doc.rust-lang.org/book/ch06-02-match.html https://doc.rust-lang.org/book/ch06-02-match.html
- aynyc 6y ago
  Looking at the examples in the doc. That’s just tuple/list unpacking in Python. Am I misreading it?
  - ketzu 6y ago
    The linked doc seems to show only what python does as tuple unpacking, but as far as I know elixir can also do the matched unpacking. Based on [1] (which also gives a more matchy example), elixir just has a warning when not using the variable in the case block and you can denote that you want to match against the contents of the variable by prepending ^. [1] https://www.reddit.com/r/programming/comments/lgqhmj/stack_overflow_users_rejoice_as_pattern_matching/gmtypn2/ https://www.reddit.com/r/programming/comments/lgqhmj/stack_o...
- fortran77 6y ago
  > If you want a great example of how it can be useful and how clear and elegant it can be, check out how it's done in Elixir [0]. If you want to see what it _really_ should look like, see Erlang, and then look at Prolog.
jml7c5 6y ago
Much more than a switch statement. Here's PEP 636, a tutorial: https://www.python.org/dev/peps/pep-0636/ https://www.python.org/dev/peps/pep-0636/
tirpen 6y ago
Yes, just like functions are just a new buzzword for goto. Structural pattern matching is a lot more than just switch/case, and I while I think pythons implementation looks imperfect, it will still be an amazing boon to the language. There are a few gotcha-edge cases, but they are of the kind that are obvious once you've encountered them once. I already know a couple dozen functions in my projects that I'm going to refactor to a fraction of their current length and improve the readability of at the same time as soon as this lands.
willxinc 6y ago
Pattern matching is distinct from switch cases, this is where the "odd" behavior people are taking issue with stems from. If it were a switch case statement, the case behavior would behave differently.

From what I gather from that article is that pattern matching is the new buzzword for Switch Cases? If so, expect an influx of applications misusing switches in replacement of if.

cassianoleal 6y ago

It's certainly not, although it can be used in switch cases. Pattern matching is a great language feature but I've been watching the development of it for Python for a while and have felt nothing but horror. If you want a great example of how it can be useful and how clear and elegant it can be, check out how it's done in Elixir [0]. There are many other languages that implement it in great ways, I'm sure others will comment on them. [0] https://elixir-lang.org/getting-started/pattern-matching.html https://elixir-lang.org/getting-started/pattern-matching.htm...

sammorrowdrums 6y ago
Yes,oddly I love it I Rust, it is probably a favourite feature, but I am not really excited about it in Python. https://doc.rust-lang.org/book/ch06-02-match.html https://doc.rust-lang.org/book/ch06-02-match.html
aynyc 6y ago
Looking at the examples in the doc. That’s just tuple/list unpacking in Python. Am I misreading it?
- ketzu 6y ago
  The linked doc seems to show only what python does as tuple unpacking, but as far as I know elixir can also do the matched unpacking. Based on [1] (which also gives a more matchy example), elixir just has a warning when not using the variable in the case block and you can denote that you want to match against the contents of the variable by prepending ^. [1] https://www.reddit.com/r/programming/comments/lgqhmj/stack_overflow_users_rejoice_as_pattern_matching/gmtypn2/ https://www.reddit.com/r/programming/comments/lgqhmj/stack_o...
fortran77 6y ago
> If you want a great example of how it can be useful and how clear and elegant it can be, check out how it's done in Elixir [0]. If you want to see what it _really_ should look like, see Erlang, and then look at Prolog.

jml7c5 6y ago

Much more than a switch statement. Here's PEP 636, a tutorial: https://www.python.org/dev/peps/pep-0636/ https://www.python.org/dev/peps/pep-0636/

tirpen 6y ago

Yes, just like functions are just a new buzzword for goto. Structural pattern matching is a lot more than just switch/case, and I while I think pythons implementation looks imperfect, it will still be an amazing boon to the language. There are a few gotcha-edge cases, but they are of the kind that are obvious once you've encountered them once. I already know a couple dozen functions in my projects that I'm going to refactor to a fraction of their current length and improve the readability of at the same time as soon as this lands.

willxinc 6y ago

Pattern matching is distinct from switch cases, this is where the "odd" behavior people are taking issue with stems from. If it were a switch case statement, the case behavior would behave differently.