Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

What you learn by making a new programming language

ntietz.com

Post reply on HN
Print view View original

31–40 of 137 posts

Re: What you learn by making a new programming language

#31

Post by emseetech »

sjducb wrote: post #20
tombert wrote: post #13

I've had two projects that end up being "oops, I made an interpreter". It starts innocently enough, you just have a JSON that has some basic functionality. Then you decide it would be cool to nest functionality because there's no reason not to, so you build a recursive parser. Then you think it'd be neat to be able to add some arguments to the recursive stuff, because then you can more easily parameterize the JSON. T…

> and life is pain So glad you finished with this. Right now I’m working with a guy who wants to write an interpreter…

Writing an interpreter for a project that isn't explicitly an interpreter is a code smell equivalent to microwaving fish.

It is an incredibly fun side project though.

Re: What you learn by making a new programming language

#32

Post by anonymoushn »

tombert wrote: post #13

I've had two projects that end up being "oops, I made an interpreter". It starts innocently enough, you just have a JSON that has some basic functionality. Then you decide it would be cool to nest functionality because there's no reason not to, so you build a recursive parser. Then you think it'd be neat to be able to add some arguments to the recursive stuff, because then you can more easily parameterize the JSON. T…

I'm pretty happy with "json scripting" for an implementation[0] of card game[1] with relatively low rules complexity. For a time it could evaluate arithmetic expressions, but I got rid of that because it was a bit unwieldy. The main pain point is that it runs slower than I'd like, so I may end up porting it all to actual Javascript functions or to Zig.

[0]: https://github.com/sharpobject/yisim/blob/master/swogi.json

[1]: https://store.steampowered.com/app/1948800/Yi_Xian_The_Culti...

Re: What you learn by making a new programming language

#33

Post by diggan »

sjducb wrote: post #20
tombert wrote: post #13

I've had two projects that end up being "oops, I made an interpreter". It starts innocently enough, you just have a JSON that has some basic functionality. Then you decide it would be cool to nest functionality because there's no reason not to, so you build a recursive parser. Then you think it'd be neat to be able to add some arguments to the recursive stuff, because then you can more easily parameterize the JSON. T…

> and life is pain So glad you finished with this. Right now I’m working with a guy who wants to write an interpreter…

> Right now I’m working with a guy who wants to write an interpreter…

Stuff like that works out great if you have a static set of features that will never change and you can at one point say "it's done", and won't have to touch it again.

Problem is that features are almost never static across their lifetime, and some poor sucker has to modify it at one point.

Re: What you learn by making a new programming language

#34

Post by jjtheblunt »

efilife wrote: post #11
shortrounddev2 wrote: post #6

Earlier quoted context omitted.

> Any sufficiently complicated C or Fortran program contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Common Lisp https://en.wikipedia.org/wiki/Greenspun%27s_tenth_rule

Is this a joke I'm not getting? Any examples of such software?

It's a famous quote and it is of course meant to be humorous, and a statement of how vast the functionality of common lisp is (huge spec and book)

Re: What you learn by making a new programming language

#35

Post by lioeters »

JohnMakin wrote: post #7

One of the most fundamental experiences I ever had was attempting a graduate level course at the end of a long series on compilers. You really get an eye opening view of how languages are translated into the language the machine understands. After going through a few toy languages and then finally tackling creating a simple JVM, here is the #1 thing I would go back to myself and scream until I was blue - Make your in…

This is why the Lisp syntax is a great candidate for an exercise in making your own language. For example, Make a Lisp. https://github.com/kanaka/mal

It's simple to lex and parse into an abstract syntax tree, so you can get on with exploring more interesting aspects of programming beyond the mere syntax. (Not to say that there aren't interesting aspects of grammar and innovative syntax, but those can probably be explored later on as macros.)

Last time I created a toy language, I implemented a C-like infix syntax but still used a Lisp evaluator at its core from a previous project.

Re: What you learn by making a new programming language

#36

Post by kbolino »

01HNNWZ0MV43FF wrote: post #23
yjftsjthsd-h wrote: post #9

Earlier quoted context omitted.

It's not its own kernel, but emacs can run on Linux as PID 1, at which point it rather seems like it should count as an OS. Given its affiliation, emacs/Linux probably still counts as GNU/Linux, but still...

I say if it's not running as the kernel, it's not an OS. Otherwise you could "boot to" any terminal app. Nano? OS. Cat? OS. Echo? Believe it or not, OS. Good grief.

PID 1 has some unique responsibilities. In particular, any process that gets orphaned when its original parent exits is automatically reparented by PID 1, and so the process running as PID 1 must watch for unexpected SIGCHILD and clean up the zombies with waitpid or similar.

Re: What you learn by making a new programming language

#38

Post by JohnMakin »

lioeters wrote: post #35
JohnMakin wrote: post #7

One of the most fundamental experiences I ever had was attempting a graduate level course at the end of a long series on compilers. You really get an eye opening view of how languages are translated into the language the machine understands. After going through a few toy languages and then finally tackling creating a simple JVM, here is the #1 thing I would go back to myself and scream until I was blue - Make your in…

This is why the Lisp syntax is a great candidate for an exercise in making your own language. For example, Make a Lisp. https://github.com/kanaka/mal It's simple to lex and parse into an abstract syntax tree, so you can get on with exploring more interesting aspects of programming beyond the mere syntax. (Not to say that there aren't interesting aspects of grammar and innovative syntax, but those can probably be expl…

> It's simple to lex and parse into an abstract syntax tree,

There are some "cheats" for this, tools like ANTLR etc. that are good at generating parsers from a particular grammar. But of course, I think a beginner should try to do this on their own to get a feel for it.

Personally, for me, I do find writing parsers a little tedious and not the most fun part of making a language.

Re: What you learn by making a new programming language

#39

Post by whartung »

JohnMakin wrote: post #7

One of the most fundamental experiences I ever had was attempting a graduate level course at the end of a long series on compilers. You really get an eye opening view of how languages are translated into the language the machine understands. After going through a few toy languages and then finally tackling creating a simple JVM, here is the #1 thing I would go back to myself and scream until I was blue - Make your in…

For many simple languages, the most complex construct is the expression.

Lots of things come to light there. Lots of recursion/fun with stacks, operator precedence, the type system, parameter passing. Pretty much a good solid chunk of language is wrapped up in expressions.

Get expressions working, and the rest starts to readily fall into place.

Re: What you learn by making a new programming language

#40

Post by aapoalas »

gavinhoward wrote: post #19
tombert wrote: post #13

I've had two projects that end up being "oops, I made an interpreter". It starts innocently enough, you just have a JSON that has some basic functionality. Then you decide it would be cool to nest functionality because there's no reason not to, so you build a recursive parser. Then you think it'd be neat to be able to add some arguments to the recursive stuff, because then you can more easily parameterize the JSON. T…

See also the Configuration Complexity Clock: https://mikehadlow.blogspot.com/2012/05/configuration-comple... . This is why I have a separate config language and code language. My config language is essentially JSON with newline separators and a first-class binary type (base64). I added little else. When I get the temptation to add code to it, I just pull out my other, general-purpose language instead.

I'm basically in charge of maintaining and developing a product that (on purpose) started at 9 o'clock. We've resisted the call to implement loops and such in our DSL but I can hear the wolves howling and I doubt I have much longer...
Post reply on HN