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0 pointsCDSlice5y ago0 comments

Although it won't be as concise, you can use guards to emulate this feature with

    match data:
        case [x1, x2] if x1 == x2:
            ...

I agree on this being a fantastic addition to the language. I've sorely missed not having pattern matching in Python after using Rust.

0 comments

spott5y ago

I think this is a better version. It is less ambiguous and more general. The [x,x] version isn't clear if it is using `__eq__` or `is`.

RhysU5y ago

Guards feel superfluous if the x, x pattern can be trivially lowered into a guard.

repsilat5y ago

More vice versa. Guards look more general (being able to express not-equal, and less-than etc), so special semantics for `x,x` only seem warranted if it's very common.

RhysU5y ago

Agreed they're more general. If I have a working guard implementation I can build the x, x case atop it. Meaning, the x, x case can be sugar.

j / k navigate · click thread line to collapse

0 pointsCDSlice5y ago0 comments

Although it won't be as concise, you can use guards to emulate this feature with

    match data:
        case [x1, x2] if x1 == x2:
            ...

I agree on this being a fantastic addition to the language. I've sorely missed not having pattern matching in Python after using Rust.

0 comments

spott5y ago

I think this is a better version. It is less ambiguous and more general. The [x,x] version isn't clear if it is using `__eq__` or `is`.

RhysU5y ago

Guards feel superfluous if the x, x pattern can be trivially lowered into a guard.

repsilat5y ago

More vice versa. Guards look more general (being able to express not-equal, and less-than etc), so special semantics for `x,x` only seem warranted if it's very common.

RhysU5y ago

Agreed they're more general. If I have a working guard implementation I can build the x, x case atop it. Meaning, the x, x case can be sugar.

j / k navigate · click thread line to collapse