Method new

std/src/help.rs:312–358

Builds an index of the given `callables` and returns a new collection of help topics.

(callables: &HashMap<SymbolKey, Rc<CallableMetadata>>)

impl Topics {
    /// Builds an index of the given `callables` and returns a new collection of help topics.
    fn new(callables: &HashMap<SymbolKey, Rc<CallableMetadata>>) -> Self {
        fn insert(topics: &mut Trie<String, Box<dyn Topic>>, topic: Box<dyn Topic>) {
            let key = topic.name().to_ascii_uppercase();
            topics.insert(key, topic);
        }

        let mut topics = Trie::default();

        {
            let mut index = BTreeMap::default();

            for (title, content) in parse_lang_reference(LANG_MD) {
                let topic = LanguageTopic { name: title, text: content };
                index.insert(topic.name.to_owned(), topic.text.lines().next().unwrap());
                insert(&mut topics, Box::from(topic));
            }

            insert(
                &mut topics,
                Box::from(CategoryTopic {
                    name: "Language reference",
                    description: "General language topics",
                    index,
                }),
            );
        }

        let mut categories = HashMap::new();
        for metadata in callables.values() {
            let category_title = metadata.category().lines().next().unwrap();
            categories.entry(category_title).or_insert_with(Vec::default).push(metadata.clone());

            let name = match metadata.return_type() {
                None => metadata.name().to_owned(),
                Some(return_type) => format!("{}{}", metadata.name(), return_type.annotation()),
            };

            insert(&mut topics, Box::from(CallableTopic { name, metadata: metadata.clone() }));
        }
        for (name, metadatas) in categories.into_iter() {
            let description = metadatas.first().expect("Must have at least one symbol").category();
            let index = callables_to_index(&metadatas);
            insert(&mut topics, Box::from(CategoryTopic { name, description, index }));
        }

        Self(topics)
    }

    /// Returns the given topic named `name`, where `name` can be a prefix.
    ///