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I'll probably try SILE just because it does not support macro.

I personally think the adoption macro is the embodiment of non intuitive programming languages and why a modern programming languages, for example Rust is supporting macro is beyond me.

I'm not alone in this regard, D a modern successor of C and C++ does not support macro.

Hopefully one day Walter will write document on "Macro Considered Harmful" to enlighten the subject.




I respect your stance (although I disagree strongly) but you might consider something other than Sile, as Chapter 6 of Sile's manual is called 'SILE Macros and Commands'. Also from reading about D, his strongest objection to using macros is that they do not respect the scope. This is probably the main source of macros' strength as code generators. Again, I respect your aversion to macros, I am not sure I understand the reasons, though.


The SILE approach for macro is very limited and sane. I think that's purposely to make sure that it's simple to understand, intuitive and maintain. More complex activities or programming is delegated to Lua as mentioned in the Simon's TUGboat paper:

> SILE’s \define command provides an extremely restricted macro system for implementing simple tags, but you are deliberately forced to write anything more complex in Lua. (Maxim: Programming tasks should be done in programming languages!)


> D a modern successor of C and C++ does not support macro.

These are macros:

https://dlang.org/articles/mixin.html


It's technically not macro as mentioned in the same page link:

>C preprocessing expressions follow a different syntax and have different semantic rules than the C language. The C preprocessor is technically a different language. Mixins are in the same language.

D shows that it's possible to be a very powerful and potent programming language for DSL, etc, without all the conventional macro abuse and misuse.

If anyone asked me how come Python has becoming very popular nowadays, the answer will be it's one of the most intuitive and user friendly programming languages ever designed, and that's mainly due to the fact that it does not support macro [1].

[1]https://news.ycombinator.com/item?id=33431843


It's not a C preprocessor macro. Those are a very specific and limited subset of macros, and that is the main reason why they're criticized.

Broadly speaking, if something can generate parametrized chunks of AST on the go, it's a macro. Which is exactly what D mixins do.

As for Python, it doesn't really need macros because everything is runtime. But if you need it, compile() and eval() are there, and they can be abused much worse than any macro facility ever could.


It really depends on your definition of macro [1]. Modern programming languages like Scala, Julia, Nim, Rust etc are supporting hygienic macro.

According to D authors Mixin is not macro because Mixin still looks like D language while supporting macro would meant the inclusion of macro (hygienic or not), and depending on the implementation, most often than not will render the language unrecognizable (become non intuitive). Again if someone is purposely writing a DSL in D for generating a new language's AST then that's perfectly fine. Essentially the output is another programming language because it is the intentional product of the exercises but the original programming language is still intuitive.

I suppose you can have runtime macro like VBA but Python language designers refused to incorporate it due to issues as mentioned beforehand.

[1]https://en.m.wikipedia.org/wiki/Macro_(computer_science)


Surely hygienic macros are a subset of macros, as follows from their name?

I still don't see why D's mixins aren't hygienic macros. And the D documentation doesn't make that claim, either - it only highlights the difference with C preprocessor, not macros in general.

OTOH I can't think of anything in VB6/VBA that resembles macros, runtime or otherwise?


Sure hygienic macro belongs to macro but saner.

Mixin is not macro according to D authors. If you dig into Walter's past posts, perhaps you can find better explanations there than mine.

You can have macro in any runtime for example Ruby language, and that's the main reason for the maxim "Rails is not Ruby". That's also the reason Ruby is so powerful and to create a similar feat in Java will be close to impossible [2]. But at what cost? That's why Python now is much more popular even though Ruby is much more powerful. You can, however, create Rails clone in D language without all the macro nonsense [3].

[1]Ruby Macros Explained:

https://codeburst.io/ruby-macros-18bb67e051c7

[2]Stop Designing Languages. Write Libraries Instead:

http://lbstanza.org/purpose_of_programming_languages.html

[3]Diamond CMS:

https://github.com/DiamondMVC




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