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doc: use nested list for Table of Contents 

A nested list is much easier to browse than a table.
Move Imports section below Arrays and Maps for Types grouping.
Move Defer section to Statements group.
Move vfmt section next to Profiling for Tools group.
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Nick Treleaven 2020-06-26 18:36:40 +01:00 committed by GitHub
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@ -17,74 +17,79 @@ you can do in V.
## Table of Contents
<table>
<tr>
<td width=16%><a href='#hello-world'>1. Hello world</a></td>
<td width=16%><a href='#comments'>2. Comments</a></td>
<td width=16%><a href='#functions'>3. Functions</a></td>
<td width=16%><a href='#variables'>4. Variables</a></td>
<td width=16%><a href='#primitive-types'>5. Primitive types</a></td>
<td width=16%><a href='#strings'>6. Strings</a></td>
</tr>
<tr>
<td><a href='#imports'>7. Imports</a></td>
<td><a href='#arrays'>Arrays</a></td>
<td><a href='#maps'>Maps</a></td>
<td><a href='#if'>If</a></td>
<td><a href='#in-operator'>In Operator</a></td>
<td><a href='#for-loop'>For loop</a></td>
</tr>
<tr>
<td><a href='#match'>Match</a></td>
<td><a href='#structs'>Structs</a></td>
<td><a href='#short-struct-initialization-syntax'>Short struct init syntax</a></td>
<td><a href='#access-modifiers'>Access modifiers</a></td>
<td><a href='#methods'>Methods</a></td>
<td><a href='#pure-functions-by-default'>Pure functions by default</a></td>
</tr>
<tr>
<td><a href='#anonymous--high-order-functions'>Anonymous & high order fns</a></td>
<td><a href='#references'>References</a></td>
<td><a href='#constants'>Constants</a></td>
<td><a href='#println'>println</a></td>
<td><a href='#modules'>Modules</a></td>
<td><a href='#interfaces'>Interfaces</a></td>
</tr>
<tr>
<td><a href='#enums'>Enums</a></td>
<td><a href='#sum-types'>Sum types</a></td>
<td><a href='#optionresult-types-and-error-handling'>Option/Result & error handling</a></td>
<td><a href='#generics'>Generics</a></td>
<td><a href='#concurrency'>Concurrency</a></td>
<td><a href='#decoding-json'>Decoding JSON</a></td>
</tr>
<tr>
<td><a href='#testing'>Testing</a></td>
<td><a href='#memory-management'>Memory managment</a></td>
<td><a href='#defer'>Defer</a></td>
<td><a href='#orm'>ORM</a></td>
<td><a href='#vfmt'>vfmt</a></td>
<td><a href='#writing-documentation'>Writing documentation</a></td>
</tr>
<tr>
<td><a href='#profiling'>Profiling</a></td>
<td><a href='#calling-c-functions-from-v'>Calling C functions from V</a></td>
<td><a href='#conditional-compilation'>Conditional compilation</a></td>
<td><a href='#compile-time-pseudo-variables'>Compile time pseudo variables</a></td>
<td><a href='#reflection-via-codegen'>Reflection via codegen</a></td>
<td><a href='#limited-operator-overloading'>Limited operator overloading</a></td>
</tr>
<tr>
<td><a href='#inline-assembly'>Inline assembly</a></td>
<td><a href='#translating-cc-to-v'>Translating C/C++ to V</a></td>
<td><a href='#hot-code-reloading'>Hot code reloading</a></td>
<td><a href='#cross-compilation'>Cross compilation</a></td>
<td><a href='#cross-platform-shell-scripts-in-v'>Cross-platform shell scripts in V</a></td>
<td><a href='#attributes'>Attributes</a></td>
</tr>
<tr>
<td><a href='#appendix-i-keywords'>Appendix I: Keywords</a></td>
<td><a href='#appendix-ii-operators'>Appendix II: Operators</a></td>
</tr>
<tr><td>
[Hello world](#hello-world)
[Comments](#comments)
[Functions](#functions)
[Variables](#variables)
[Types](#types)
* [Primitive types](#primitive-types)
* [Strings](#strings)
* [Arrays](#arrays)
* [Maps](#maps)
[Imports](#imports)
[Statements & Expressions](#statements--expressions)
* [If](#if)
* [In Operator](#in-operator)
* [For loop](#for-loop)
* [Match](#match)
* [Defer](#defer)
[Structs](#structs)
* [Short struct init syntax](#short-struct-initialization-syntax)
* [Access modifiers](#access-modifiers)
* [Methods](#methods)
[println](#println)
</td><td>
[Functions 2](#functions-2)
* [Pure functions by default](#pure-functions-by-default)
* [Anonymous & high order functions](#anonymous--high-order-functions)
[References](#references)
[Modules](#modules)
[Constants](#constants)
[Types 2](#types-2)
* [Interfaces](#interfaces)
* [Enums](#enums)
* [Sum types](#sum-types)
* [Option/Result types & error handling](#optionresult-types-and-error-handling)
[Generics](#generics)
[Concurrency](#concurrency)
[Decoding JSON](#decoding-json)
[Testing](#testing)
[Memory management](#memory-management)
[ORM](#orm)
[Writing documentation](#writing-documentation)
[Tools](#tools)
* [vfmt](#vfmt)
* [Profiling](#profiling)
</td><td>
[Advanced](#advanced)
* [Calling C functions from V](#calling-c-functions-from-v)
* [Conditional compilation](#conditional-compilation)
* [Compile time pseudo variables](#compile-time-pseudo-variables)
* [Reflection via codegen](#reflection-via-codegen)
* [Limited operator overloading](#limited-operator-overloading)
* [Inline assembly](#inline-assembly)
* [Translating C/C++ to V](#translating-cc-to-v)
* [Hot code reloading](#hot-code-reloading)
* [Cross compilation](#cross-compilation)
* [Cross-platform shell scripts in V](#cross-platform-shell-scripts-in-v)
* [Attributes](#attributes)
[Appendices](#appendices)
* [Keywords](#appendix-i-keywords)
* [Operators](#appendix-ii-operators)
</td></tr>
</table>
@ -270,7 +275,9 @@ fn main() {
Unlike most languages, variable shadowing is not allowed. Declaring a variable with a name that is already used in a parent scope will cause a compilation error.
## Primitive types
## Types
### Primitive types
```v
bool
@ -313,7 +320,7 @@ or `i64` but not to `f32` or `u32`. (`f32` would mean precission
loss for large values and `u32` would mean loss of the sign for
negative values).
## Strings
### Strings
```v
name := 'Bob'
@ -379,20 +386,7 @@ s := r'hello\nworld'
println(s) // "hello\nworld"
```
## Imports
```v
import os
fn main() {
name := os.input('Enter your name:')
println('Hello, $name!')
}
```
Modules can be imported using keyword `import`. When using types, functions, and constants from other modules, the full path must be specified. In the example above, `name := input()` wouldn't work. That means that it's always clear from which module a function is called.
## Arrays
### Arrays
```v
mut nums := [1, 2, 3]
@ -455,7 +449,7 @@ println(upper) // ['HELLO', 'WORLD']
`it` is a builtin variable which refers to element currently being processed in filter/map methods.
## Maps
### Maps
```v
mut m := map[string]int // Only maps with string keys are allowed for now
@ -473,7 +467,22 @@ numbers := {
}
```
## If
## Imports
```v
import os
fn main() {
name := os.input('Enter your name:')
println('Hello, $name!')
}
```
Modules can be imported using keyword `import`. When using types, functions, and constants from other modules, the full path must be specified. In the example above, `name := input()` wouldn't work. That means that it's always clear from which module a function is called.
## Statements & Expressions
### If
```v
a := 10
@ -503,7 +512,7 @@ else {
println(s) // "odd"
```
## In operator
### In operator
`in` allows to check whether an array or a map contains an element.
@ -530,7 +539,7 @@ if parser.token in [.plus, .minus, .div, .mult] {
V optimizes such expressions, so both `if` statements above produce the same machine code and no arrays are created.
## For loop
### For loop
V has only one looping construct: `for`.
@ -603,7 +612,7 @@ stuck in an infinite loop.
Here `i` doesn't need to be declared with `mut` since it's always going to be mutable by definition.
## Match
### Match
```v
os := 'windows'
@ -645,6 +654,24 @@ fn is_red_or_blue(c Color) bool {
A match statement can also be used to branch on the variants of an `enum`
by using the shorthand `.variant_here` syntax.
### Defer
A defer statement defers the execution of a block of statements until the surrounding function returns.
```v
fn read_log() {
f := os.open('log.txt')
defer { f.close() }
...
if !ok {
// defer statement will be called here, the file will be closed
return
}
...
// defer statement will be called here, the file will be closed
}
```
## Structs
```v
@ -710,7 +737,7 @@ All struct fields are zeroed by default during the creation of the struct. Array
It's also possible to define custom default values.
## Short struct initialization syntax
### Short struct initialization syntax
There are no default function argument values or named arguments, for that the short struct initialization syntax can be used instead:
@ -747,7 +774,7 @@ new_button(ButtonConfig{text:'Click me', width:100})
This only works with functions that have a single struct argument.
## Access modifiers
### Access modifiers
Struct fields are private and immutable by default (making structs immutable as well).
Their access modifiers can be changed with
@ -792,7 +819,7 @@ fn main() {
This means that defining public readonly fields is very easy in V, no need in getters/setters or properties.
## Methods
### Methods
```v
struct User {
@ -820,7 +847,9 @@ In this example, the `can_register` method has a receiver of type `User` named `
The convention is not to use receiver names like `self` or `this`,
but a short, preferably one letter long, name.
## Pure functions by default
## Functions 2
### Pure functions by default
V functions are pure by default, meaning that their return values are a function of their arguments only,
and their evaluation has no side effects.
@ -885,7 +914,7 @@ fn register(u User) User {
user = register(user)
```
## Anonymous & high order functions
### Anonymous & high order functions
```v
fn sqr(n int) int {
@ -1088,7 +1117,9 @@ fn init() int {
The init function cannot be public. It will be called automatically.
## Interfaces
## Types 2
### Interfaces
```v
struct Dog {}
@ -1124,7 +1155,7 @@ println(perform(cat)) // "meow"
A type implements an interface by implementing its methods.
There is no explicit declaration of intent, no "implements" keyword.
## Enums
### Enums
```v
enum Color {
@ -1137,7 +1168,7 @@ color = .green
println(color) // "1" TODO: print "green"?
```
## Sum types
### Sum types
```v
type Expr = BinaryExpr | UnaryExpr | IfExpr
@ -1213,7 +1244,7 @@ There are 3 ways to access the cast variant inside a match branch:
Note: shadowing only works when the match expression is a variable. It will not work on struct fields, arrays indexing, or map key lookup.
## Option/Result types and error handling
### Option/Result types and error handling
```v
struct User {
@ -1430,24 +1461,6 @@ fn test() []int {
}
```
## Defer
A defer statement defers the execution of a block of statements until the surrounding function returns.
```v
fn read_log() {
f := os.open('log.txt')
defer { f.close() }
...
if !ok {
// defer statement will be called here, the file will be closed
return
}
...
// defer statement will be called here, the file will be closed
}
```
## ORM
(this is still in an alpha state)
@ -1495,20 +1508,6 @@ sql db { insert new_customer into Customer }
For more examples, see <a href='https://github.com/vlang/v/blob/master/vlib/orm/orm_test.v'>vlib/orm/orm_test.v</a>.
## vfmt
You don't need to worry about formatting your code or setting style guidelines.
`vfmt` takes care of that:
```v
v fmt file.v
```
It's recommended to set up your editor, so that vfmt runs on every save.
A vfmt run is usually pretty cheap (takes <30ms).
Always run `v fmt -w file.v` before pushing your code.
## Writing Documentation
The way it works is very similar to Go. It's very simple: there's no need to
@ -1529,7 +1528,23 @@ An overview of the module must be placed in the first comment right after the mo
To generate documentation use vdoc, for example `v doc net.http`.
## Profiling
## Tools
### vfmt
You don't need to worry about formatting your code or setting style guidelines.
`vfmt` takes care of that:
```v
v fmt file.v
```
It's recommended to set up your editor, so that vfmt runs on every save.
A vfmt run is usually pretty cheap (takes <30ms).
Always run `v fmt -w file.v` before pushing your code.
### Profiling
V has good support for profiling your programs: `v -profile profile.txt run file.v`
That will produce a profile.txt file, which you can then analyze.
@ -2016,6 +2031,8 @@ fn C.WinFunction()
```
# Appendices
## Appendix I: Keywords
V has 23 keywords: