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Dear sir, you have built a compiler

rachitnigam.com

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Re: Dear sir, you have built a compiler

#11

Post by jasfi »

olivierduval wrote: post #3

I'm always surprised by the lack of "easy" parser/compiler toolkit for more or less complete DSL... It looks like there's only - either full blown programming language for IT guys - "natural language" AI toolkits (not really usable yet for just simple automation by users) - graphical language like State Machine or "no code", missing loops and requiring mouse and boxes However, most of the time, user simply need some…

What about ANTLR?

Re: Dear sir, you have built a compiler

#12

Post by sunir »

I think you should almost always build a compiler when presented with a parse then execute problem. It is so much faster to create a small machine that is fed data to specific the program, and a test harness that also drives that machine, then it is to hand code every little case repetitively.

Or maybe I like building little compilers.

Re: Dear sir, you have built a compiler

#13

Post by voidmain0001 »

jacquesm wrote: post #5
olivierduval wrote: post #3

I'm always surprised by the lack of "easy" parser/compiler toolkit for more or less complete DSL... It looks like there's only - either full blown programming language for IT guys - "natural language" AI toolkits (not really usable yet for just simple automation by users) - graphical language like State Machine or "no code", missing loops and requiring mouse and boxes However, most of the time, user simply need some…

There's Forth. Many would argue it's not a full blown programming language, it's more like a toolkit to make DSLs.

There's also Eric Lippert's blog series on OOP and business rules [1] that culminates [2] in suggesting a DSL with Inform7 as a possible candidate. The comments on the final post are great as people rail against the use of a DSL.

[1] https://ericlippert.com/2015/04/27/wizards-and-warriors-part...

[2] https://ericlippert.com/2015/05/11/wizards-and-warriors-part...

Re: Dear sir, you have built a compiler

#14

Post by 3pt14159 »

This is a great article, and if I were writing path-critical code for the situation the author describes I'd use an AST too, but I still munge me some text and most of the time it's good enough.

The problem with using AST libraries is that they're hard to understand unless you're used to them. So if you have to choose between a couple hundred lines of python or ruby and a giant AST I think it's smarter to go with the ruby. That way when something like a new emoji comes out, or what have you, the junior dev can handle the minor bug fix. Your AST is still going to choke on it. No way around it, the world has changed.

That said, there is an art to writing text processors and keeping things sane. The most important bit I've learned is to avoid transformations during extractions even at the cost of performance. At least until a fully exhaustive test suite is up. It makes it easier to test and it's a clearer separation of responsibilities.

I've written a lot of these parsers. One for a custom format for the Nasdaq on a project I was the lead on! I shudder to think of how many bits that thing is processing since it pipes data to and from thousands of data brokers and hedge funds.

Re: Dear sir, you have built a compiler

#16

Post by olivierduval »

jasfi wrote: post #11
olivierduval wrote: post #3

I'm always surprised by the lack of "easy" parser/compiler toolkit for more or less complete DSL... It looks like there's only - either full blown programming language for IT guys - "natural language" AI toolkits (not really usable yet for just simple automation by users) - graphical language like State Machine or "no code", missing loops and requiring mouse and boxes However, most of the time, user simply need some…

What about ANTLR?

Actually, I was thinking about having an "already build" BASIC language... not creating a new one each time.

As a programmer, you would include the libray, provide the binding to your program... and done ! In a way, it's a bit what is possible with java.scripting but they provide a Javascript engine but no BASIC for end-user

Re: Dear sir, you have built a compiler

#17

Post by brandmeyer »

olivierduval wrote: post #3

I'm always surprised by the lack of "easy" parser/compiler toolkit for more or less complete DSL... It looks like there's only - either full blown programming language for IT guys - "natural language" AI toolkits (not really usable yet for just simple automation by users) - graphical language like State Machine or "no code", missing loops and requiring mouse and boxes However, most of the time, user simply need some…

The intermediate solution is a programming language and/or runtime specifically designed as an extension system. I've had positive experiences embedding Lua. GNU Guile was specifically designed for this too, if you think your users can deal with the parens.

Re: Dear sir, you have built a compiler

#18

Post by TillE »

YAGNI is a good principle here. Whenever I've found myself thinking about reaching for a parser library, I was over-complicating or over-generalizing the problem. Write the code you need to solve the problem you actually have.

Re: Dear sir, you have built a compiler

#20

Post by rachitnigam »

olivierduval wrote: post #3

I'm always surprised by the lack of "easy" parser/compiler toolkit for more or less complete DSL... It looks like there's only - either full blown programming language for IT guys - "natural language" AI toolkits (not really usable yet for just simple automation by users) - graphical language like State Machine or "no code", missing loops and requiring mouse and boxes However, most of the time, user simply need some…

Racket is often heralded as the "programming language programming language" and comes with tons of features to build full blown languages: https://racket-lang.org/

The most complete language/ecosystem that really showcases Racket's capabilities is Rosette IMO: https://github.com/emina/rosette/

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