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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

#71

Post by mrlemke »

orthoxerox wrote: post #28
mrlemke wrote: post #21

Earlier quoted context omitted.

Sounds like a gap TCL could fill. The syntax is simple and consistent, a developer could create packages that a non-developer end user can use as commands, and it could be wrapped with GUI code that runs on Windows, Mac, or Linux.

Tcl is good, but non-developers could really benefit from more write-time checks. Something that can tell them "there's no command called moveRight, the nearest match is move-right" before their script is executed.

I agree. I would really like the same. Komodo IDE may help with this, but I haven't tried it. I usually end up in vim due to habit.

Re: Dear sir, you have built a compiler

#72

Post by eulers_secret »

hobofan wrote: post #31

I feel like you can apply the same sentiment to many of the "big scary things" in programming. Things that you don't want to build (as far as "common engineering wisdom" is to be believed): - a compiler - a programming language (not sure that there is a difference to compiler as stated in the article) - a database (query engine) - a CMS - a ERP But sometimes you actually _do_ want to build that (even if every alarm b…

> …But sometimes you actually _do_ want to build that…

That’s not true for everyone. I’ve been a dev for 20 years and have never done any of those, and I have no desire to at all. That is ok! Programming isn’t some kind of progression to run from “n00b hello world” to “1337 compiler hax0r”, it’s a tool to solve problems with. Many of us will never have to solve these problems or have no interest in these problems.

So, if you’re like me, don’t worry because you’ve never made a brainfuck interpreter or a database engine. It doesn’t mean you’re a bad dev. You can have a successful career without building these! And if you need them some time, learn them at that time… you may not ever need to.

Re: Dear sir, you have built a compiler

#73

Post by shadowgovt »

lupire wrote: post #37

https://en.m.wikipedia.org/wiki/Greenspun%27s_tenth_rule "Any sufficiently complicated C or Fortran program contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Common Lisp." (Same applies to popular languages after the original quote.)

What often goes unsaid is the corollary: "Any Common Lisp implementation people use contains an ad-hoc, informally-specified, bug-ridden optimizing compiler written in C or Fortran."

Re: Dear sir, you have built a compiler

#74

Post by blacksqr »

mrlemke wrote: post #21
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…

Sounds like a gap TCL could fill. The syntax is simple and consistent, a developer could create packages that a non-developer end user can use as commands, and it could be wrapped with GUI code that runs on Windows, Mac, or Linux.

Linked article appears to be describing the exact original motivation for writing Tcl:

"My students and I had written several interactive tools for IC design, such as Magic and Crystal. Each tool needed to have a command language (in those days people tended to invoke tools by typing commands; graphical user interfaces weren't yet in widespread use). However, our primary interest was in the tools, not their command languages. Thus we didn't invest much effort in the command languages and the languages ended up being weak and quirky. Furthermore, the language for one tool couldn't be carried over to the next, so each tool ended up with a different bad command language. After a while this became tiresome and embarrassing."

https://web.stanford.edu/~ouster/cgi-bin/tclHistory.php

Re: Dear sir, you have built a compiler

#75

Post by emteycz »

YeGoblynQueenne wrote: post #24
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 Prolog and its Definite Clause Grammars (DCG) formalism. Here's a DCG for a tiny subset of natural English (copied from wikipedia [1]): sentence --> noun_phrase, verb_phrase. noun_phrase --> det, noun. verb_phrase --> verb, noun_phrase. det --> [the]. det --> [a]. noun --> [cat]. noun --> [bat]. verb --> [eats]. The syntax is just like BNF. "-->" is "::=", terms in []'s are terminals and the rest are nontermi…

Awesome!

Do you have any recommendations for good articles about Prolog? I really like the idea. I'm particularly interested in solving assignment problems using constraint logic programming.

Re: Dear sir, you have built a compiler

#77

Post by rachitnigam »

____________g wrote: post #59
eatonphil wrote: post #44

It's a hilarious post but I'm scared and curious to ask what this is in response to?

Yes, I agree. It feels like some context is missing here.

[OP] Ah, I've just seen a bunch of people showcase "amazing new tools" that are just bad compilers in disguise. State of the art Database query optimizers are good examples of this.

Re: Dear sir, you have built a compiler

#78

Post by wpietri »

jasoncabot wrote: post #56

This reminds me of a great post about the typical software evolution going from hard coded values, through configuration and rules engines to a DSL, only to be back where you started. I have seen it happen on multiple projects, it’s hard to spot it at the time as all the changes seem sensible but hindsight is a wonderful thing http://mikehadlow.blogspot.com/2012/05/configuration-complex...

This line really struck me: “They will have to change at some point, and you don’t want to recompile and redeploy your application just to change the VAT tax rate.”

Continuous deployment has changed this for me. I'm still not going to leave tunable constants in the middle of random if statements. But nowadays instead of trying to avoid recompiling and redeploying, I'd rather invest that time into making that very easy.

Re: Dear sir, you have built a compiler

#79

Post by chubot »

mattgreenrocks wrote: post #67
agumonkey wrote: post #62

Earlier quoted context omitted.

does it affect how you code other kinds of apps too ? knowing how to think about a program interpretation space gives quite a broader view IMO

I'd argue the idea of an "interpreter" is one of the most foundational concepts of CS. It sounds really basic, but the idea of being handed a description, and doing/creating something based on that is everywhere . It is really quite beautiful.

IIRC it's even in the "Design Patterns" book -- the Interpreter pattern. It really does come up a lot.
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