doc: document new features in V and Veb

Author: medvednikov

doc/docs.md

@@ -54,6 +54,24 @@ If V is already installed on a machine, it can be upgraded to its latest version
 by using the V's built-in self-updater.
 To do so, run the command `v up`.
 
+## Project-local compiler versions with `.vvmrc`
+
+If a project contains a `.vvmrc` file, commands like `v run .`, `v run file.v`,
+or `v file.v` will try to find and delegate to the requested V compiler version.
+This makes it easier to keep a project pinned to a known compiler release.
+
+The file should contain one version per project, for example:
+
+```text
+0.4.12
+```
+
+Both `0.4.12` and `v0.4.12` are accepted. The special aliases `latest` and
+`current` keep using the currently running compiler.
+
+V searches for `.vvmrc` from the target path upward and stops at repository and
+project boundaries such as `.git`, `.hg`, `.svn`, and `.v.mod.stop`.
+
 ## Packaging V for distribution
 See the [notes on how to prepare a package for V](packaging_v_for_distributions.md) .
 
@@ -487,6 +505,10 @@ fn main() {
 }
 ```
 
+The compiler also warns about obviously constant conditions, for example
+self-comparisons like `if x == x { ... }` or `match` branches that can never be
+reached. These warnings help catch redundant checks and dead branches early.
+
 To ignore values returned by a function `_` can be used
 ```v
 fn foo() (int, int) {
@@ -3624,12 +3646,12 @@ To define a new type `NewType` as an alias for `ExistingType`,
 do `type NewType = ExistingType`.<br/>
 This is a special case of a [sum type](#sum-types) declaration.
 
-Numeric aliases can use empty literal syntax for zero/default initialization:
+Numeric aliases use ordinary conversions for initialization:
 
 ```v
 type Decimal = f64
 
-amount := Decimal{}
+amount := Decimal(0.0)
 ```
 
 ### Enums
@@ -4219,6 +4241,23 @@ if mut w is Mars {
 
 Otherwise `w` would keep its original type.
 > This works for both simple variables and complex expressions like `user.name`
+> and `values[i]`.
+
+Smart casts also work on indexed expressions in `match` branches:
+
+```v oksyntax
+type Entry = int | string
+
+values := [Entry('v')]
+match values[0] {
+	string {
+		assert values[0] == 'v'
+	}
+	else {
+		assert false
+	}
+}
+```
 
 #### Matching sum types
 
@@ -4336,7 +4375,7 @@ fn main() {
 Trailing option-typed parameters can also be omitted in function calls.
 When they are not passed, V supplies `none`:
 
-```v
+```v ignore
 fn connect(url string, timeout ?int) {
 	actual_timeout := timeout or { 1000 }
 	println('${url} -> ${actual_timeout}')

vlib/veb/README.md

@@ -8,7 +8,11 @@ features.
 - **Very fast** performance of C on the web.
 - **Templates are precompiled** all errors are visible at compilation time, not at runtime.
 - **Middleware** functionality similar to other big frameworks.
+- **HTTPS support** directly from `veb` via `mbedtls`.
+- **Method-aware route middleware** for protecting only selected HTTP verbs.
+- **Static compression** with gzip/zstd, including manual pre-compression support.
 - **Controllers** to split up your apps logic.
+- **Graceful shutdown** support in the `new_veb` backend.
 - **Easy to deploy** just one binary file that also includes all templates. No need to install any
   dependencies.
 
@@ -119,6 +123,18 @@ fn main() {
 }
 ```
 
+## Graceful shutdown
+
+When running with `-d new_veb`, the underlying server supports graceful
+shutdown. Once shutdown begins, it stops accepting new requests, waits for
+in-flight requests to finish, and only then exits. This is useful for deploys,
+tests, and management endpoints that trigger a stop after sending a response.
+
+The lifecycle controls come from the underlying `fasthttp.ServerHandle`
+(`wait_till_running()` and `shutdown(timeout: ...)`). If you need explicit
+server lifecycle management, use those lower-level hooks in the process that
+starts your app.
+
 ## Defining endpoints
 
 To add endpoints to your web server, you must extend the `App` struct.
@@ -469,8 +485,8 @@ over gzip when the client supports both.
 1. **Manual pre-compression**: If you create `.zst` or `.gz` files manually, veb will serve
    them in zero-copy streaming mode for maximum performance when the MIME type is allowed.
 2. **Lazy compression cache**: Files smaller than the threshold are automatically compressed
-   on first request and cached as `.zst` or `.gz` files on disk (zstd preferred when client
-   supports it).
+   on first request and cached under `os.cache_dir()/veb/static_compression/`
+   (zstd preferred when the client supports it). The source directory stays unchanged.
 3. **Cache validation**: If the original file is modified, the compressed cache is
    automatically regenerated on the next request.
 4. **Streaming for large files**: Files larger than the threshold are served uncompressed in
@@ -561,8 +577,8 @@ curl -H "Accept-Encoding: zstd, gzip" --compressed http://localhost:8080/app.js
 # Request without encoding - should return uncompressed content
 curl -i http://localhost:8080/app.js
 
-# Verify that compressed cache file was created
-ls -lh static/app.js.zst static/app.js.gz 2>/dev/null
+# Auto-generated cache files are stored under:
+# os.cache_dir()/veb/static_compression/
 
 # Test manual pre-compression - style.css.zst is served directly (zero-copy)
 curl -H "Accept-Encoding: zstd" -i http://localhost:8080/style.css
@@ -579,6 +595,8 @@ serve `.zst` if the client supports zstd, otherwise `.gz` if gzip is supported.
 
 - The lazy cache is created on first request, so the first visitor pays a small
   compression cost, but all subsequent requests are served at zero-copy speed.
+- Auto-generated cache files live in the OS cache directory, so read-only static
+  folders still work and your source tree stays clean.
 - Large files (> threshold) are always streamed, ensuring low memory usage even for large assets.
 - The `encode_auto` middleware automatically chooses zstd or gzip based on client support. You can
   also use `encode_zstd` or `encode_gzip` for specific compression.
@@ -1165,4 +1183,4 @@ fn main() {
 	mut app := &App{}
 	veb.run[App, Context](mut app, 8080)
 }
-```
+```