Code Generation

Perry's code generation pipeline: Widget Tree → Backend → Native Source Code.

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Backends

11 platform code generators, each implementing CodegenBackend:

Backend	Class	Platforms	Output
swiftui	SwiftUIBackend	macOS, iOS, tvOS, visionOS, watchOS	SwiftUI Swift
html	HtmlBackend	Web, WebAssembly	HTML/CSS/JavaScript
compose	ComposeBackend	Android	Jetpack Compose Kotlin
android-xml	AndroidXmlBackend	Android	Android XML layouts
winui	WinUIBackend	Windows	WPF/WinUI XAML
gtk4	Gtk4Backend	Linux	GTK4 XML UI
arkts	ArkTsBackend	HarmonyOS	ArkUI TypeScript
glance	GlanceBackend	Android (home screen)	Kotlin Glance composables
wear-tiles	WearTilesBackend	Wear OS	Kotlin TileService
flutter	FlutterBackend	Flutter	Dart widget tree
wasm	WasmBackend	WebAssembly	HTML + JS bridge API

Usage

use Perry\App;
use Perry\Build\Target;

$app = new App();
$app->setRoot($widgetTree);

// By name
echo $app->generateCode('swiftui');
echo $app->generateCode('html');

// Auto-detect from target
$app = new App(Target::fromString('macos'));
echo $app->generateForTarget();

// Write to file
$backend = $app->codegen()->get('html');
$backend->generateToFile($widgetTree, 'build/output.html');

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Generators

Generators transform IR nodes (Intermediate Representation) into target language code. Each implements Perry\IR\Generator with 50+ methods.

Generator	Language	State Variable	New Variable
SwiftGenerator	Swift	name = ...	var name = ...
JavaScriptGenerator	JavaScript	state.name = ...	let name = ...
KotlinGenerator	Kotlin	name.value = ...	var name = ...
DartGenerator	Dart	name.value = ...	var name = ...
CSharpGenerator	C#	name = ...	var name = ...

Usage

use Perry\Generator\SwiftGenerator;
use Perry\IR\Assignment;
use Perry\IR\Literal;

$gen = new SwiftGenerator(stateVars: ['display', 'result']);
$ir = new Assignment('display', new Literal('Hello'));
echo $gen->generateAssignment($ir);
// Output: display = "Hello"

$ir2 = new Assignment('count', new Literal(42));
echo $gen->generateAssignment($ir2);
// Output: var count = 42  (new variable, not a state var)

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IR System

54 intermediate representation node types represent PHP code in a language-agnostic form:

Core (14)

Program, Assignment, IfStatement, BinaryOp, UnaryOp, Variable, Literal, FunctionCall, ReturnStatement, ArrayAccess, MethodCall, PropertyAccess, Ternary, ArrayLiteral

Loops (5)

WhileStatement, ForStatement, ForeachStatement, BreakStatement, ContinueStatement

Switch/Match (3)

SwitchStatement, CaseNode, MatchExpression

Output (2)

EchoStatement, PrintStatement

Type System (1)

Cast

Inc/Dec (2)

Increment, Decrement

Compound Assignment (5)

PlusAssign, MinusAssign, MulAssign, DivAssign, ModAssign

Binary Ops (11)

PowOp, BitwiseAnd, BitwiseOr, BitwiseXor, ShiftLeft, ShiftRight, SpaceshipOp, CoalesceOp, LogicalAnd, LogicalOr, LogicalXor

Unary Ops (2)

UnaryPlus, BitwiseNot

Nullsafe (2)

NullsafeMethodCall, NullsafePropertyAccess

Exceptions (3)

ThrowStatement, TryCatchStatement, CatchClause

Static (3)

StaticCall, StaticPropertyAccess, ClassConstFetch

Other (1)

IncludeStatement

Pipeline

PHP Closure
    │
    ▼ nikic/php-parser
PHP AST
    │
    ▼ Perry\IR\AstToIrVisitor
Perry IR (54 node types)
    │
    ▼ Perry\Generator\{Swift,JavaScript,Kotlin,Dart,CSharp}Generator
Target Language Code