mirror of
https://github.com/typst/typst
synced 2025-08-20 01:48:34 +08:00
39 lines
1.2 KiB
Rust
39 lines
1.2 KiB
Rust
use crate::diag::SourceResult;
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use crate::engine::Engine;
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use crate::foundations::{elem, Content, Packed, Show, StyleChain, Value};
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use crate::introspection::Locatable;
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/// Exposes a value to the query system without producing visible content.
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///
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/// This element can be retrieved with the [`query`] function and from the
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/// command line with
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/// [`typst query`]($reference/introspection/query/#command-line-queries). Its
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/// purpose is to expose an arbitrary value to the introspection system. To
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/// identify a metadata value among others, you can attach a [`label`] to it and
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/// query for that label.
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///
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/// The `metadata` element is especially useful for command line queries because
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/// it allows you to expose arbitrary values to the outside world.
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///
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/// ```example
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/// // Put metadata somewhere.
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/// #metadata("This is a note") <note>
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///
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/// // And find it from anywhere else.
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/// #context {
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/// query(<note>).first().value
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/// }
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/// ```
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#[elem(Show, Locatable)]
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pub struct MetadataElem {
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/// The value to embed into the document.
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#[required]
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pub value: Value,
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}
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impl Show for Packed<MetadataElem> {
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fn show(&self, _: &mut Engine, _styles: StyleChain) -> SourceResult<Content> {
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Ok(Content::empty())
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}
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}
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