rust-search-extension/README.md

![](assets/rustacean.png)

# Rust Search Extension

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A handy browser extension to search crates and docs in address bar (omnibox).

### Features

- Search Primitive Types and Modules
- Search Structs, Traits and Enums
- Search Functions, Methods and Macros
- Search crates on https://crates.io

### Usages

Input keyword **rs** in address bar, press `Tab` or `Space` to active the search bar.
Then enter any word you want to search, the extension will response the related search
results in few seconds. 

![demonstration.gif](assets/demonstration.gif)

### How the extension works

##### 1. Build *search index*

The raw *search index* was generated by **rustc-doc**. The most important function is `build_index()` which 
located at [librustdoc/html/render.rs](https://github.com/rust-lang/rust/blob/master/src/librustdoc/html/render.rs).

The final *search index* is a object array like this:

```js
var searchIndex = [
    {
      crate: "std",
      desc: "The `Option` type. See the module level documentation for more.",
      displayPath: "std::option::",
      fullPath: "std::option::Option",
      href: "https://doc.rust-lang.org/std/option/enum.Option.html",
      lev: 0,
      name: "Option",
      parent: undefined,
      path: "std::option",
      ty: 4,
      type: null
    },
    {
        crate: "std",
        desc: "Applies function to the elements of iterator and returns the first non-none result.",
        name: "find_map",
        parent: {ty: 8, name: "Iterator"},
        path: "std::iter",
        ty: 11,
        type: [["self"],["f"]]
    }
    ...
]
```
 
##### 2. Build *search words array* based on *search index*

The *search words array* is the list of search words to query against which build from the raw *search index*.
It's just a plain name array of every Rust structs, traits, enums, functions, methods, macros, etc.
```js
var searchWords = [
    "result", 
    "option", 
    "hashmap", 
    "hashset", 
    "clone", 
    "copy", 
    "disply", 
    "debug",
    ...
]
```

##### 3. Search keyword in *search words array* by *levenshtein distance*, mapping the *search word* and *search index* to generate the *search result*

##### 4. Sort *search result* according to *levenshtein distance* and others metrics

##### 5. Transform *search result* to *suggestion result* to show in address bar