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XML is a cheap DSL

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Re: XML is a cheap DSL

#141

Post by necovek »

xienze wrote: post #52
Someone1234 wrote: post #50

Earlier quoted context omitted.

I keep seeing people make the same mistake as XML made over and over; without learning from it. I will clarify the problem thusly: > The more capabilities you add to a interchange format, the harder that format is to parse. There is a reason why JSON is so popular, it supports so little, that it is legitimately easy to import. Whereas XML supports attributes, namespaces, CDATA, DTDs, QNames, xml:base, xml:lang, XIncl…

> Whereas XML supports attributes, namespaces, CDATA, DTDs, QNames, xml:base, xml:lang, XInclude, etc etc. They gave it everything, including the kitchen sink. But you don't have to use all those things. Configure your parser without namespace support, DTD support, etc. I'd much rather have a tool with tons of capabilities that can be selectively disabled rather than a "simple" one that requires _me_ to bolt on said…

If you do not go with DTD or XSD, you are only doing XML lookalike language, as these are XML mechanisms to really define the XML schema: a compliant parser won't be able to validate it, or maybe even to parse it.

Thus people go with custom parsers (how hard can it be, right?), and then have to keep fixing issues as someone or other submits an XML with CDATA in or similar.

Re: XML is a cheap DSL

#142

Post by n_e »

catlifeonmars wrote: post #131
n_e wrote: post #129

Earlier quoted context omitted.

The "data" is part of the tax simulation source code, not untrusted input, so such an attack vector doesn't exist.

Yet. You’re adding one other thing that authors need to keep in mind when developing the product, fixing bugs, and adding features. The fact that the input must be trusted is not an intrinsic part of the business logic, it’s an additional caveat that humans need to remember.

What exactly do the developers need to keep in mind?

Re: XML is a cheap DSL

#143

Post by himata4113 »

himata4113 wrote: post #23
Hackbraten wrote: post #20

At the cost of a slightly more complex schema, the JSON representation can be made much more readable: { "path": "/tentativeTaxNetNonRefundableCredits", "description": "Total tentative tax after applying non-refundable credits, but before applying refundable credits.", "maxOf": [ { "const": { "value": 0, "currency": "Dollar" } }, { "subtract": { "from": "/totalTentativeTax", "amount": "/totalNonRefundableCredits" } }…

YAML seems like a great middleground here between xml and json..

lots of haters when openspec is yaml(and json), k8s is yaml, most of go is yaml actually. sure I know it has faults, but it's really nice to type.

Re: XML is a cheap DSL

#144

Post by phlakaton »

conartist6 wrote: post #117
GuB-42 wrote: post #103

Earlier quoted context omitted.

I think JSON has the opposite problem, it is too simple, the lack of comments in particular is particularly bad for many common usages of the format today. I know some implementations of JSON support comments and other things, but is is not true JSON, in the same way that most simple XML implementations are not true XML. That's what I say "opposite problem", XML is too complex, and most practical uses of XML use inco…

A lot of people dislike that decision not to include comments in JSON, but I think while shocking it was and is totally correct. In a programming language it's usually free to have comments because the comment is erased before the program runs; we usually render comments in grey text because they can't change the meaning of the program. In a data language you have no such luxury. In a data language there's no comment…

I don't dislike the decision at all, FWIW! For data interchange it's totally reasonable. But it does make JSON ill-suited for a bunch of applications that JSON has been forcefully and unfortunately applied to.

Re: XML is a cheap DSL

#145

Post by maccard »

quotemstr wrote: post #132
Someone1234 wrote: post #50

Earlier quoted context omitted.

I keep seeing people make the same mistake as XML made over and over; without learning from it. I will clarify the problem thusly: > The more capabilities you add to a interchange format, the harder that format is to parse. There is a reason why JSON is so popular, it supports so little, that it is legitimately easy to import. Whereas XML supports attributes, namespaces, CDATA, DTDs, QNames, xml:base, xml:lang, XIncl…

> XML supports attributes, namespaces, CDATA, DTDs, QNames, xml:base, xml:lang, XInclude, etc etc. They gave it everything, including the kitchen sink. Ah, the old "throw a bag of nouns at the reader and hope he's intimidated" rhetorical flutist. These things are either non-issues (like QName), things a parser does for you, or optional standards adjacent to XML but not essential to it, e.g. XInclude.

> Ah, the old "throw a bag of nouns at the reader and hope he's intimidated" rhetorical flutist.

The accusation here is a defleciton. OP's point isn't a gish gallop, it's that xml is absolutely littered with edge cases and complexities that all need to be understood.

> optional standards adjacent to XML but not essential

This is exactly OP's point. The standard is everything and the kitchen sink, except for all the bits it doesn't include which are almost imperceptible from the actual standard because of how widely used they are.

Re: XML is a cheap DSL

#146

Post by gaigalas »

PunchyHamster wrote: post #119
Someone1234 wrote: post #50

Earlier quoted context omitted.

I keep seeing people make the same mistake as XML made over and over; without learning from it. I will clarify the problem thusly: > The more capabilities you add to a interchange format, the harder that format is to parse. There is a reason why JSON is so popular, it supports so little, that it is legitimately easy to import. Whereas XML supports attributes, namespaces, CDATA, DTDs, QNames, xml:base, xml:lang, XIncl…

Constant erosion of data formats into the shittiest DSLs in existence is annoying. "Oh, hey, instead of writing Python, how about you write in * YAML, with magical keywords that turn data into conditions/commands * template language for the YAML in places when that isn't enough * ....Python, because you need to eventually write stuff that ingests the above either way .... ansible is great isn't it?" ... and for some…

Basic dicts, arrays and templates might be the killer feature set for declarative data languages. If everyone coalesces to those eventually, it means there's something to it.

Re: XML is a cheap DSL

#147

Post by necovek »

alexpetros wrote: post #47
necovek wrote: post #7

XML is notoriously expensive to properly parse in many languages. Basically, the entire world centers around 3 open source implementations (libxml2, expat and Xerces), if you want to get anywhere close to actual compliance. Even with them, you might hit challenges (libxml2 was largely unmaintained recently, yet it is the basis for many bindings in other languages). The main property of SGML-derived languages is that…

Author here. I agree with all this, and I think it's important to note that nothing precludes you from doing a declarative specification that looks like imperative math notation, but it's also somewhat besides the point. Yes, you could make your own custom language, but then you have created the problem that the article is about: You need to port your parser to every single different place you want to use it. That's…

You are right that your other examples (like s-expressions) are actually better than going with a fully custom language.

But as you note elsewhere, you were benefiting from the schema (DTD or XSD) being done elsewhere, which provided at least some validation: in my experience, building this layer (either in code or with a new DTD/XSD) without a proper XML schema is the hardest part in doing XML well.

By ignoring this cost, it appeared much cheaper than it really is.

I also think including proper XML parsing libraries (which are sometimes huge) is not always feasible either (think embedded devices, or even if you need to package it with your mobile app, the size will be relatively big).

Re: XML is a cheap DSL

#148

Post by quotemstr »

maccard wrote: post #145
quotemstr wrote: post #132

Earlier quoted context omitted.

> XML supports attributes, namespaces, CDATA, DTDs, QNames, xml:base, xml:lang, XInclude, etc etc. They gave it everything, including the kitchen sink. Ah, the old "throw a bag of nouns at the reader and hope he's intimidated" rhetorical flutist. These things are either non-issues (like QName), things a parser does for you, or optional standards adjacent to XML but not essential to it, e.g. XInclude.

> Ah, the old "throw a bag of nouns at the reader and hope he's intimidated" rhetorical flutist. The accusation here is a defleciton. OP's point isn't a gish gallop, it's that xml is absolutely littered with edge cases and complexities that all need to be understood. > optional standards adjacent to XML but not essential This is exactly OP's point. The standard is everything and the kitchen sink, except for all the b…

XInclude isn't part of the standard, and IME, a minority of systems support it anyway. The OP's comment is an obvious gish-gallop. You can assemble a similarly scary noun list for practically any technology.

Probably the same kind of person who tries to praise JSON's lack of comments as a feature or something.

Re: XML is a cheap DSL

#149

Post by [deleted] »

quotemstr wrote: post #132
Someone1234 wrote: post #50

Earlier quoted context omitted.

I keep seeing people make the same mistake as XML made over and over; without learning from it. I will clarify the problem thusly: > The more capabilities you add to a interchange format, the harder that format is to parse. There is a reason why JSON is so popular, it supports so little, that it is legitimately easy to import. Whereas XML supports attributes, namespaces, CDATA, DTDs, QNames, xml:base, xml:lang, XIncl…

> XML supports attributes, namespaces, CDATA, DTDs, QNames, xml:base, xml:lang, XInclude, etc etc. They gave it everything, including the kitchen sink. Ah, the old "throw a bag of nouns at the reader and hope he's intimidated" rhetorical flutist. These things are either non-issues (like QName), things a parser does for you, or optional standards adjacent to XML but not essential to it, e.g. XInclude.

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