This is sad because as Json seems to be taking over. Despite its terseness Json lacks a standardized way to do validation (ie xsd), transformations (ie xslt) and service definitions (ie wsdl).

Its regrettable that such a vast ecosystem exists for a markup language to facilitate its use in data transfer, transformation and validation.

It seems like a waste that so many working standards seem to have just been tossed away with nothing to put into their place because Json saves a few bits on the wire.

Also regrettable is the fact that there seems to be resistance in developing similar standards for json.

Json is not popular because it saves bits but because it's easily readable and maps 1:1 with js objects. I've worked with xml and xslt and while I see the advantages I still prefer json for anything. Your validation should come from annotated objects on the backend anyways which should be a single source of truth and then it doesn't matter which markup format you are validating

I can kind of see what you're saying, but what does "annotated objects on the backend" mean. If there is not a standard I can only hack a solution together. I cannot ensure anything with 100% certainty, instead I'm left guessing if my logic is correct.

With a standard, however, I can be sure that what I intend is being validated and if my logic is wrong then I can change it to match the spec.

Json schema maybe http://json-schema.org/

The tooling did/does leave a lot to be desired in XML workflows. I think, in XML's heyday, it was way easier to template with PHP/ASP/JSP on the server. While those languages could have just as easily spit out XML to be transformed on the client, writing the XSL was non-trivial and lacked good tools to make the process easier.

I find JSON to be a lackluster replacement for XML. The efforts to bolt on XML features (JSON Schema etc.) are half assed and not widely supported. Without a bunch of extra complication you can't really know what a value in JSON means beyond its translation to some primitive.

The web development world doesn't deserve XML! /s

I am a bit of an XML fanboy as it solves complicated problems in a logical way. I also bought into (and continue to believe) in a lot of Web 2.0 ideas beyond pastel colors and pseudo-reflections on logos.