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+
+Prerequisites:
+
+In order to build the VS Code plugin, you need to have node.js and npm with
+a minimum version of 10 installed. Please refer to
+[node.js and npm documentation](https://nodejs.org) for installation instructions.
+
+You will also need the most recent version of VS Code: we don't try to
+maintain compatibility with older versions yet.
+
+The experimental VS Code plugin can then be built and installed by executing the
+following commands:
+
+```
+$ git clone https://github.com/rust-analyzer/rust-analyzer.git --depth 1
+$ cd rust-analyzer
+$ cargo install-code
+
+# for stdlib support
+$ rustup component add rust-src
+```
+
+This will run `cargo install --package ra_lsp_server` to install the server
+binary into `~/.cargo/bin`, and then will build and install plugin from
+`editors/code`. See
+[this](https://github.com/rust-analyzer/rust-analyzer/blob/0199572a3d06ff66eeae85a2d2c9762996f0d2d8/crates/tools/src/main.rs#L150)
+for details. The installation is expected to *just work*, if it doesn't, report
+bugs!
+
+It's better to remove existing Rust plugins to avoid interference.
+
+## Rust Analyzer Specific Features
+
+These features are implemented as extensions to the language server protocol.
+They are more experimental in nature and work only with VS Code.
+
+### Syntax highlighting
+
+It overrides built-in highlighting, and works only with a specific theme
+(zenburn). `rust-analyzer.highlightingOn` setting can be used to disable it.
+
+### Go to symbol in workspace <kbd>ctrl+t</kbd>
+
+It mostly works on top of the built-in LSP functionality, however `#` and `*`
+symbols can be used to narrow down the search. Specifically,
+
+- `#Foo` searches for `Foo` type in the current workspace
+- `#foo#` searches for `foo` function in the current workspace
+- `#Foo*` searches for `Foo` type among dependencies, excluding `stdlib`
+- `#foo#*` searches for `foo` function among dependencies.
+
+That is, `#` switches from "types" to all symbols, `*` switches from the current
+workspace to dependencies.
+
+### Commands <kbd>ctrl+shift+p</kbd>
+
+#### Show Rust Syntax Tree
+
+Shows the parse tree of the current file. It exists mostly for debugging
+rust-analyzer itself.
+
+#### Extend Selection
+
+Extends the current selection to the encompassing syntactic construct
+(expression, statement, item, module, etc). It works with multiple cursors. Do
+bind this command to a key, its super-useful! Expected to be upstreamed to LSP soonish:
+https://github.com/Microsoft/language-server-protocol/issues/613
+
+#### Matching Brace
+
+If the cursor is on any brace (`<>(){}[]`) which is a part of a brace-pair,
+moves cursor to the matching brace. It uses the actual parser to determine
+braces, so it won't confuse generics with comparisons.
+
+#### Parent Module
+
+Navigates to the parent module of the current module.
+
+#### Join Lines
+
+Join selected lines into one, smartly fixing up whitespace and trailing commas.
+
+#### Run
+
+Shows popup suggesting to run a test/benchmark/binary **at the current cursor
+location**. Super useful for repeatedly running just a single test. Do bind this
+to a shortcut!
+
+
+### On Typing Assists
+
+Some features trigger on typing certain characters:
+
+- typing `let =` tries to smartly add `;` if `=` is followed by an existing expression.
+- Enter inside comments automatically inserts `///`
+- typing `.` in a chain method call auto-indents
+
+
+### Code Actions (Assists)
+
+These are triggered in a particular context via light bulb. We use custom code on
+the VS Code side to be able to position cursor.
+
+
+- Flip `,`
+
+```rust
+// before:
+fn foo(x: usize,<|> dim: (usize, usize))
+// after:
+fn foo(dim: (usize, usize), x: usize)
+```
+
+- Add `#[derive]`
+
+```rust
+// before:
+struct Foo {
+    <|>x: i32
+}
+// after:
+#[derive(<|>)]
+struct Foo {
+    x: i32
+}
+```
+
+- Add `impl`
+
+```rust
+// before:
+struct Foo<'a, T: Debug> {
+    <|>t: T
+}
+// after:
+struct Foo<'a, T: Debug> {
+    t: T
+}
+
+impl<'a, T: Debug> Foo<'a, T> {
+    <|>
+}
+```
+
+- Change visibility
+
+```rust
+// before:
+fn<|> foo() {}
+
+// after
+pub(crate) fn foo() {}
+```
+
+- Introduce variable:
+
+```rust
+// before:
+fn foo() {
+    foo(<|>1 + 1<|>);
+}
+
+// after:
+fn foo() {
+    let var_name = 1 + 1;
+    foo(var_name);
+}
+```
+
+- Replace if-let with match:
+
+```rust
+// before:
+impl VariantData {
+    pub fn is_struct(&self) -> bool {
+        if <|>let VariantData::Struct(..) = *self {
+            true
+        } else {
+            false
+        }
+    }
+}
+
+// after:
+impl VariantData {
+    pub fn is_struct(&self) -> bool {
+        <|>match *self {
+            VariantData::Struct(..) => true,
+            _ => false,
+        }
+    }
+}
+```
+
+- Split import
+
+```rust
+// before:
+use algo:<|>:visitor::{Visitor, visit};
+//after:
+use algo::{<|>visitor::{Visitor, visit}};
+```
+
+## LSP features
+
+* **Go to definition**: works correctly for local variables and some paths,
+  falls back to heuristic name matching for other things for the time being.
+
+* **Completion**: completes paths, including dependencies and standard library.
+  Does not handle glob imports and macros. Completes fields and inherent
+  methods.
+
+* **Outline** <kbd>alt+shift+o</kbd>
+
+* **Signature Info**
+
+* **Format document**. Formats the current file with rustfmt. Rustfmt must be
+  installed separately with `rustup component add rustfmt`.
+
+* **Hover** shows types of expressions and docstings
+
+* **Rename** works for local variables
+
+* **Code Lens** for running tests
+
+* **Folding**
+
+* **Diagnostics**
+  - missing module for `mod foo;` with a fix to create `foo.rs`.
+  - struct field shorthand
+  - unnecessary braces in use item
+
+
+## Performance
+
+Rust Analyzer is expected to be pretty fast. Specifically, the initial analysis
+of the project (i.e, when you first invoke completion or symbols) typically
+takes dozen of seconds at most. After that, everything is supposed to be more or
+less instant. However currently all analysis results are kept in memory, so
+memory usage is pretty high. Working with `rust-lang/rust` repo, for example,
+needs about 5 gigabytes of ram.