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flow - @type and @lazy

Let’s highlight two new features in flow arrived with hexMachina 0.27.0.

Force typing in flow DSL with new @type

By default, every object instancied in DSL use his own type as property type. With the new @type flow keyword is possible to apply another type to the property. Not to be confused with @map_type use to map object in ApplicationContext injector.

@context()
{
    @type( 'hex.log.ILogger' )
    logger = new hex.log.Logger( loggerContext, "myLogger");

    loggerContext = hex.log.LoggerContext.getContext();
}

Is equal to that in haxe :

class hex.context.applicationContext implements hex.context.IapplicationContext_0 {

	public var loggerContext:hex.log.LoggerContext;
	public var logger:hex.log.ILogger;

	public function m_dcea6fa1359cfeff3f1f1e4264791aa7() {
		var loggerContext = hex.log.LoggerContext.getContext();
		this.loggerContext = loggerContext;
		var logger = new hex.log.Logger(loggerContext, "myLogger");
		this.logger = logger;
	}
}

Define lazy instanciation in flow DSL with @lazy

Declaration with @lazy metadata will not be executed until is used somewhere. context/flow/primitives/lazyInt.flow - link

@context( name = 'applicationContext' )
{
	@lazy
	i = hex.mock.LazyProvider.provide( -3 );
	
	@lazy
	o = new hex.mock.LazyClass( 'test' );
}

test/hex/mock/LazyClass.hx - link

class LazyClass 
{
	public static var value : Any;
	
	public function new( o : Any ) 
	{
		LazyClass.value = o;
	}
}

test/hex/mock/LazyProvider.hx - link

class LazyProvider 
{
	public static var value : Any;
	
	public function new() {}
	
	public static function provide<T>( o : T ) : T
	{
		LazyProvider.value = o;
		return o;
	}
}

@Test( “test building lazy primitive” ) - link

@Test( "test building lazy primitive" )
public function testBuildingLazyInt() : Void
{
	var code = BasicStaticFlowCompiler.compile( this._myApplicationAssembler, "context/flow/primitives/lazyInt.flow", "BasicStaticFlowCompiler_testBuildingLazyInt" );
	LazyProvider.value = null;
	LazyClass.value = null;
	code.execute();
	
	Assert.isNull( LazyProvider.value );
	Assert.equals( -3, code.locator.i );
	Assert.equals( -3, LazyProvider.value );
	
	Assert.isNull( LazyClass.value );
	Assert.isNotNull( code.locator.o );
	Assert.equals( 'test', LazyClass.value );
}

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