Advanced Compilers: Self-Guided Online Course

Post by WalterBright » Sat, Dec 12, 2020, 2:59 AM UTC

Kranar wrote: post #165

WalterBright wrote: post #160

Earlier quoted context omitted.

I suppose we could argue about the definition of context free, but the compiler lexes it without any reference to the parser, and the parser builds the AST without any reference to symbols or semantic meaning. > spell checking ... using context-free parsers Only up to a point. D's spell checker uses the symbols in scope as its "dictionary". This means it is very good at guessing what you meant instead of what is type…

A context free grammar has a formal and rigorous definition. One way to see that Dlang does not have a strictly context free grammar for its AST is the following snippet of code: A[B] C; That is parsed differently depending on whether B is a constant integer expression in which case it parses to the declaration of an array of type A with a size of B, or whether B is a typename in which case it parses into an hash map…

Post by ibains » Sat, Dec 12, 2020, 3:54 AM UTC

chrisseaton wrote: post #95

ibains wrote: post #59

I’ve worked on multiple compilers (optimizations expert) at MSFT on VS and CUDA and gave developed a DSL and worked on Database Compilers. I can’t hire compiler people with right skills. We’re building an IDE and those parsers are written differently, and we use Scala packrat parser combinators. These courses teach very little judgement or industry relevant stuff. When do you use packrat parser vs LALR vs LL? Good lu…

> Good luck hiring an engineer with advanced compiler courses knowing any of this. Have you tried raising the level of compensation you offer? There are engineers elsewhere doing this at other companies you could presumably get if you put your hands in your pockets?

Post by ibains » Sat, Dec 12, 2020, 4:54 AM UTC

vector_spaces wrote: post #96

ibains wrote: post #59

I’ve worked on multiple compilers (optimizations expert) at MSFT on VS and CUDA and gave developed a DSL and worked on Database Compilers. I can’t hire compiler people with right skills. We’re building an IDE and those parsers are written differently, and we use Scala packrat parser combinators. These courses teach very little judgement or industry relevant stuff. When do you use packrat parser vs LALR vs LL? Good lu…

I saw this great interview recently with Anders Hejlsberg at MSFT on how modern compiler construction differs from what is taught in traditional University courses. Is this what you're alluding to? After watching that interview, it's strange to read a comment like yours. While the architecture is completely different, it doesn't frankly seem like that big a leap to go from "senior engineer with X years working on thi…

Post by munificent » Sat, Dec 12, 2020, 5:08 AM UTC

cambalache wrote: post #173

munificent wrote: post #161

Earlier quoted context omitted.

> No offence, but parsing (in a compiler, not in general) is probably the most boring part of a compiler. Not if you're writing an IDE. Writing a batch mode parser that takes an entire correct source file and produces an AST is easy. Writing a parser that instaneously handle producing an updating AST while the user is typing in the middle of the program while still allowing semantic analysis to occur and without vomi…

He didnt say easy, he did say boring, and I agree.

Post by weakfish » Sat, Dec 12, 2020, 5:32 AM UTC

petr_tik wrote: post #166

nojvek wrote: post #154

I wish they’d be more courses on compilers that also serve as language servers. The current world is moving towards a phase where a language needs IDE tooling such as compilers, linters, formatters, REPL, language servers, debuggers and profilers. Would love to see a high level course that covers how to build the tooling for a great developer experience.

As i mentioned in another thread, a uni course that has students work on an existing codebase instead of writing something from scratch might be even better - though harder to grade. Imagine if one could do a major feature contribution to clangd/pyls/rust-analyzer as part of their advanced compilers course. The student gets a better understanding of (open-source) software development practices, gains a deeper profici…