This example generates a constructor-function for each field of a class to easily create value object classes.
import haxe.macro.Expr; import haxe.macro.Context; @:remove @:autoBuild(ValueClassImpl.build()) extern interface ValueClass {} class ValueClassImpl { #if macro public static function build() { var fields = Context.getBuildFields(); var args = []; var states = []; for (f in fields) { switch (f.kind) { case FVar(t,_): args.push({name:f.name, type:t, opt:false, value:null}); states.push(macro $p{["this", f.name]} = $i{f.name}); f.access.push(APublic); default: } } fields.push({ name: "new", access: [APublic], pos: Context.currentPos(), kind: FFun({ args: args, expr: macro $b{states}, params: [], ret: null }) }); return fields; } #end }
It is using an interface ValueClass marked with @:remove and extern so that it is 100% compile time only.
Usage
Create a class that implements ValueClass.
class ABC implements ValueClass { var a: Int; var b: Bool; var c: String; }
Will be compiled as:
class ABC extends ValueClass { public var a(default, null): Int; public var b(default, null): Bool; public var c(default, null): String; public function new(a: Int, b: Bool, c: String) { this.a = a; this.b = b; this.c = c; } }
