Add support for .. in let pattern matching for structs (alternative take)
#36
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Kijewski
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| = note: this error originates in the derive macro `Template` (in Nightly builds, run with -Z macro-backtrace for more info) | ||
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| error: failed to parse template source at row 2, column 17 near: |
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This error message got worse, should precise that a comma is missing.
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Absolutely right. I added a new helper function collect_targets that has better error messages likely errors such as missing a comma.
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Yes no problem. Your code is SO MUCH better, thanks a lot! Just some nits and suggestions for better error messages but it's really details at this point. |
Thank you! I loved compiler construction during my studies, and I'm always happy when I find an excuse to still dabble into that field nowadays.
Yes, I think good error messages make all the difference. It's a meme that rust tells you with subpixel accuracy where your mistakes are and how to fix them, and we should embrace it. :) |
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| #[derive(Template)] | ||
| #[template(source = " | ||
| {%- if let X { a, 1 } = x -%}hello {{ a }}{%- endif -%} |
| #[template(source = " | ||
| {%- if let X { a, 1 } = x -%}hello {{ a }}{%- endif -%} | ||
| ", ext = "html")] | ||
| struct T3 { |
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Just thought about another case:
let X { a, .., b } = x
and also:
let X { .., a } = x
I suppose the parsing will fail but better ensure the errors are good.
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I expanded the error message a bit to give better information how to use the .. in named structs.
Glad you're enjoying it! 😄
Definitely! askama's great, but error messages were terrible. I'm glad things improved to this point already. We can still do better and I think we will! |
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Great work, thanks a lot! |
This is an alternative solution to implement rest patters
..for struct or tuple targets. I think this implementation is a little bit easier to read and understand. I hope it's OK that I opened a new PR!Closes #35.