4 ms·

I am a big fan of Ragel[1]. That is a high performance parser generator. In fact, it can generate different types of parsers, very powerful. Unfortunately, it t

by gritzko 10mo ago

I am a big fan of Ragel[1]. That is a high performance parser generator. In fact, it can generate different types of parsers, very powerful. Unfortunately, it takes a lot of skill to operate. I wrote a parser generator generator to make it all smooth[2], but after 8 years I still can't call it effortless. A colleague of mine once "broke the internet" with a Ragel bug. So, think twice. Still, for weekend activities I highly recommend it, just for the way of thinking it embodies. [1]: https://www.colm.net/open-source/ragel/ https://www.colm.net/open-source/ragel/ [2]: https://github.com/gritzko/librdx/blob/master/rdx/JDR.lex https://github.com/gritzko/librdx/blob/master/rdx/JDR.lex

fuzztester 10mo ago
Is this the same Ragel that Zed Shaw wrote about in one of his posts back in the day, during Ruby and Rails heydays? I vaguely remwmber that article. I think he used it for Mongrel, his web server. https://github.com/mongrel/mongrel https://github.com/mongrel/mongrel
sph 10mo ago
The worst part of designing a language is the parsing stage. Simple enough to do it by hand, but there’s a lot of boilerplate and bureaucracy involved that is painfully time-wasting unless you know exactly what syntax you are going for. But if you adopt a parser-generator such as Flex/Bison you’ll find yourself learning and debugging and obtuse language that has to be forcefully bent to your needs, and I hope your knowledge of parsing theory is up-to-scratch when you’re facing with shift-reduce conflicts or have to decide whether LR or LALR(1) or whatever is most appropriate to your syntax. Not even PEG is gonna come to your rescue.
- fuzztester 10mo ago
  how is the boilerplate etc related to the syntax. not clear. i would have thought you first decide the syntax n only then start the work. but i've never created an interpreter, let alone a compiler.

by gritzko 10mo ago

fuzztester 10mo ago

Is this the same Ragel that Zed Shaw wrote about in one of his posts back in the day, during Ruby and Rails heydays? I vaguely remwmber that article. I think he used it for Mongrel, his web server. https://github.com/mongrel/mongrel https://github.com/mongrel/mongrel

sph 10mo ago

The worst part of designing a language is the parsing stage. Simple enough to do it by hand, but there’s a lot of boilerplate and bureaucracy involved that is painfully time-wasting unless you know exactly what syntax you are going for. But if you adopt a parser-generator such as Flex/Bison you’ll find yourself learning and debugging and obtuse language that has to be forcefully bent to your needs, and I hope your knowledge of parsing theory is up-to-scratch when you’re facing with shift-reduce conflicts or have to decide whether LR or LALR(1) or whatever is most appropriate to your syntax. Not even PEG is gonna come to your rescue.

fuzztester 10mo ago
how is the boilerplate etc related to the syntax. not clear. i would have thought you first decide the syntax n only then start the work. but i've never created an interpreter, let alone a compiler.