sdecl

sdecl is a small declarative language for tree-shaped data.

It is designed to be:

• compact
• fast
• easy to parse
• convenient for UI markup, config files, and build descriptions

The core of the language provides a typed AST with nodes, metadata, constructor arguments, typed values, attributes, and children.

Syntax

App("demo") #root {
    title = "Hello"
    width = 800
    flags = [true, false, null]
    position = { x: 10 y: 20 }

    @meta(debug)
    Button("OK") #ok {
        text = "OK"
    }

    {
        visible = true
    }
}

Rules:

• Type { ... } creates a node with explicit type
• Type(arg1, arg2) { ... } creates a node with constructor-like arguments
• #name { ... } creates a node with implicit Node type
• { ... } creates a node with implicit type and no name
• @meta and @meta(...) attach metadata to the next node
• attr = value defines an attribute
• foo.bar { ... } is parsed as a single dotted node type

Supported value kinds:

• null
• true / false
• identifiers
• integers and floats
• quoted strings
• arrays: [a, b, 1]
• objects: { key: value }

Supported number forms:

• decimal integers: 0, 10, -1
• decimal floats: 1.2, 2., -.5
• decimal exponent form: 4.5e1, -5.e2
• binary integers: 0b10
• octal integers: 0o23
• hexadecimal integers: 0x10
• base-prefixed numbers with exponent: 0o23e2

Reserved attribute names:

• type
• name
• children

Haxe API

import s.decl.Node;
import s.decl.Value;

var root = Node.parse(source);
var fileRoot = Node.parseFile("example.sdecl");

Each parsed node contains:

• type:String
• name:String
• meta:Array<{name:String, params:Array<Value>}>
• arguments:Array<Value>
• attributes:Map<String, Value>
• children:Array<Node>

Value supports:

• VNull
• VBool
• VIdent
• VInt
• VFloat
• VString
• VArray
• VObject

Development

Run tests:

haxe build_tests.hxml