Vala Reference Manual

Vala is a high level programming language that produces binaries for the native platform. The binaries maintain the C Application Binary Interface (ABI) and can be built as either an application or a library.

The Vala Reference Manual gives details on Vala's syntax and type system, including polymorphism using interfaces and type parameters (generics). Vala includes additional code generation routines, for example D-Bus inter-process communication and GTK+3 composite templates, these are only referred to in the Attributes section. The reference manual does not provide a tutorial for these features.

Vala is developed in a collaborative and self-supporting way by its users. They provide bug reports, documentation, patches, patch reviews and core development. Following this model of development the manual has an editable version at https://wiki.gnome.org/Projects/Vala/Manual .

• 1. Overview
  • 1.1 Getting started
  • 1.2 Documentation conventions
  • 1.3 Vala source files
  • 1.4 Vala conventions
  • 1.5 Vala syntax
  • 1.6 GType and GObject
  • 1.7 Memory management
  • 1.8 Vala compilation
  • 1.9 Application entry point
• 2. Concepts
  • 2.1 Variables, fields and parameters
  • 2.2 Scope and naming
  • 2.3 Object oriented programming
  • 2.4 References and ownership
• 3. Types
  • 3.1 Value types
  • 3.2 Reference types
  • 3.3 Parameterised types
  • 3.4 Nullable types
  • 3.5 Pointer types
  • 3.6 Type conversions
• 4. Expressions
  • 4.1 Literal expressions
  • 4.2 Member access
  • 4.3 Element access
  • 4.4 Arithmetic operations
  • 4.5 Relational operations
  • 4.6 Increment/decrement operations
  • 4.7 Logical operations
  • 4.8 Bitwise operations
  • 4.9 Assignment operations
  • 4.10 Invocation expressions
  • 4.11 Class instantiation
  • 4.12 Struct instantiation
  • 4.13 Array instantiation
  • 4.14 Conditional expressions
  • 4.15 Coalescing expressions
  • 4.16 Flag operations
  • 4.17 Type operations
  • 4.18 Ownership transfer expressions
  • 4.19 Lambda expressions
  • 4.20 Pointer expressions
• 5. Statements
  • 5.1 Simple statements
  • 5.2 Variable declaration
  • 5.3 Selection statements
  • 5.4 Iteration statements
  • 5.5 Jump Statements
  • 5.6 Try Statement
  • 5.7 Lock Statement
  • 5.8 Unlock Statement
  • 5.9 With Statement
• 6. Namespaces
  • 6.1 The global namespace
  • 6.2 Namespace declaration
  • 6.3 Members
  • 6.4 Fields
  • 6.5 Constants
  • 6.6 The "using" statement
• 7. Methods
  • 7.1 Parameter directions
  • 7.2 Method declaration
  • 7.3 Invocation
  • 7.4 Scope
  • 7.5 Lambdas
  • 7.6 Contract programming
• 8. Delegates
  • 8.1 Types of delegate
  • 8.2 Delegate declaration
  • 8.3 Using delegates
  • 8.4 Examples
• 9. Errors
  • 9.1 Error throwing
  • 9.2 Error catching
  • 9.3 Examples
• 10. Classes
  • 10.1 Types of class
  • 10.2 Types of class members
  • 10.3 Class scope
  • 10.4 Class member visibility
  • 10.5 Class declaration
  • 10.6 Controlling instantiation
  • 10.7 Construction
  • 10.8 Class fields
  • 10.9 Class constants
  • 10.10 Class methods
  • 10.11 Properties
  • 10.12 Signals
  • 10.13 Class enums
  • 10.14 Class delegates
  • 10.15 Examples
• 11. Interfaces
  • 11.1 Interface declaration
  • 11.2 Interface fields
  • 11.3 Interface methods
  • 11.4 Interface properties
  • 11.5 Interface signals
  • 11.6 Other interface members
  • 11.7 Examples
• 12. Generics
  • 12.1 Generics declaration
  • 12.2 Instantiation
  • 12.3 Examples
• 13. Structs
  • 13.1 Struct declaration
  • 13.2 Controlling instantiation
  • 13.3 Struct fields
  • 13.4 Struct constants
  • 13.5 Struct methods
  • 13.6 Examples
• 14. Enumerated types (Enums)
  • 14.1 Enum declaration
  • 14.2 Enum members
  • 14.3 Methods
  • 14.4 Flag types
  • 14.5 Error domains
  • 14.6 Examples
• 15. Attributes
  • 15.1 Applying attributes
  • 15.2 CCode Attribute
  • 15.3 Version attribute
  • 15.4 SimpleType attribute
  • 15.5 BooleanType Attribute
  • 15.6 IntegerType Attribute
  • 15.7 FloatingType Attribute
  • 15.8 Signal Attribute
  • 15.9 Description Attribute
  • 15.10 DBus Attribute
  • 15.11 Gtk attributes
  • 15.12 Other attributes
  • 15.13 Deprecated Attributes
  • 15.14 Examples
• 16. Preprocessor
  • 16.1 Directives syntax
  • 16.2 Defining symbols
  • 16.3 Built-in defines
  • 16.4 Examples
• 17. GIDL metadata format
  • 17.1 Comments
  • 17.2 Other Lines
  • 17.3 Specifiers
  • 17.4 Specifying Different Things
  • 17.5 Properties Reference
  • 17.6 Examples
• 18. GIR metadata format
  • 18.1 Locating metadata
  • 18.2 Comments
  • 18.3 Syntax
  • 18.4 Valid arguments
  • 18.5 Examples