feat: port syntax guide + add some info (#125)

Author: Tbusk

docs/.vitepress/config.js

@@ -1057,6 +1057,10 @@ export default {
                             {
                                 text: 'String Sample',
                                 link: '/developer-guides/string-sample'
+                            },
+                            {
+                                text: 'Syntax Guide',
+                                link: '/developer-guides/syntax-guide'
                             }
                         ]
                     },

docs/developer-guides/index.md

@@ -25,4 +25,6 @@
 - [Type Modules](plugins/01-type-modules)
 - [Libpeas](plugins/02-libpeas)
 
-#### [String Sample](string-sample)
+#### [String Sample](string-sample)
+
+#### [Syntax Guide](syntax-guide)

docs/developer-guides/syntax-guide.md

@@ -0,0 +1,79 @@
+# Syntax Guide
+
+Original Source: [Vala Syntax Guide](https://wiki.gnome.org/Projects/Vala/Syntax)
+
+The syntax of Vala is similar to C#, modified to better fit the GObject type system. Vala supports modern language features as the following:
+
+- OOP (classes, abstract classes, mixin interfaces, type polymorphism)
+- Namespaces
+- Delegates
+- Properties
+- Signals
+- Property change notifications
+- Foreach
+- Lambda expressions / Closures
+- Type inference for local variables
+- Generics
+- Non-null types
+- Assisted memory management (automatic reference counting)
+- Deterministic destructors (suitable for RAII)
+- Exception handling (checked exceptions)
+- Asynchronous methods (coroutines)
+- Preconditions and postconditions (contract programming)
+- Run-time type information
+- Named constructors
+- Verbatim strings and string templates
+- Array and string slicing
+- Conditional compilation
+- Dynamic and static D-Bus support
+- C# like syntax
+- C ABI compatibility
+- Experimental:
+  - Chained relational expressions
+  - Regular expression literals
+  - Main blocks
+
+## Keywords
+
+- Selection: `if, else, switch, case, default`
+- Iteration: `do, while, for, foreach, in`
+- Jumping: `break, continue, return`
+- Exception Handling: `try, catch, finally, throw`
+- Synchronization: `lock, unlock`
+- Type Declaration: `class, interface, struct, enum, delegate, errordomain`
+- Type Modifiers: `const, weak, unowned, dynamic`
+- Modifiers: `abstract, virtual, override, signal, extern, static, async, inline, new, sealed, partial`
+- Access Modifiers: `public, private, protected, internal`
+- Method Parameters: `out, ref`
+- Method Contract Keywords: `throws, requires, ensures`
+- Namespaces: `namespace, using`
+- Operator Keywords: `as, is, in, new, delete, sizeof, typeof`
+- Access Keywords: `this, base`
+- Literal Keywords: `null, true, false`
+- Property Context: `get, set, construct, default, value`
+- Construction Blocks: `construct, static construct, class construct`
+- Other: `void, var, yield, global, owned, with`
+
+## Operators
+
+- Arithmetic: `+`, `-`, `*`, `/`, `%`
+- Bitwise: `~`, `&`, `|`, `^`, `<<`, `>>`
+- Relational: `<`, `>`, `<=`, `>=`
+- Equality: `==`, `!=`
+- Logic: `!`, `&&`, `||`
+- Assignment: `=`, `+=`, `-=`, `*=` , `/=`, `%=`, `&=`, `|=`, `^=`, `<<=`, `>>=`
+- Increment, Decrement: `++`, `--`
+- Pointer: `&`, `*`, `->`, `delete`
+- Conditional: `?:`
+- Null-Coalescing: `??`
+- String Concatenation: `+`
+- Method Invocation: `()`
+- Member Access: `.`
+- Index: `[]`
+- Slice: `[:]`
+- Lambda: `=>`
+- Casting: `(`_Type_`)`, `(!)`, `as`
+- Type Checking: `is`
+- Ownership Transfer: `(owned)`
+- Namespace Alias Qualifier: `::` (currently only with `global`)
+- Other: `new`, `sizeof`, `typeof`, `in`