Structural subtyping in macro

This function gets @:build

-ed to display JSON objects . It works great when there is only one JSON file or all files have the same field structure. But when the object structures are different I get structural subtyping errors ("Object requires field xxx"). Also, the order of the objects matters sometimes.

I don't understand why it is type-checking; you think they will be announcements and will be left alone. Can anyone see if I am doing something right; otherwise I'll make a question on Github.

public static function build():Array<Field> {

    var fields = Context.getBuildFields();

    // Object requires field "deep"
    var files = ['{"name": "Test1", "id": { "deep" : 5 }}','{"name": "Test0","id": {}}'];

    // no error
    // var files = ['{"name": "Test0","id": {}}','{"name": "Test1", "id": { "deep" : 5 }}'];

    var a:Array<Expr> = [];
    for (s in files) {
        var o = Context.parseInlineString(s, Context.currentPos());
        a.push({ expr : EBinop(OpArrow, macro $v{s}, o), pos : Context.currentPos() });
    }

    var newfield:Field = {
        name : "files", doc : null, meta : [], access : [AStatic, APublic], pos : Context.currentPos(),
        // map array decl: [x => y]
        kind : FVar(macro : StringMap<Dynamic>, { expr : EArrayDecl(a), pos : Context.currentPos() } )
    };

    fields.push(newfield);

    return fields;
}

      

I am using Haxe 3.2.0-rc2.

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