Taking the Pain Out of Debugging With Live Programming

angry tapir writes "'Everyone knows that debugging is twice as hard as writing a program in the first place,' Brian Kernighan once wrote (adding: 'So if you're as clever as you can be when you write it, how will you ever debug it?') However, Sean McDirmid, a researcher at Microsoft, has been working to remove some of the pain from debugging. McDirmid, based at Microsoft Research Asia, has been studying ways of implementing usable live programming environments: a solution that is less intrusive than classical debuggers. The idea is to essentially provide a programming environment in which editing of code and the execution of code occur simultaneously — and in the same interface as code editing — with tools to track the state of variables in a more or less live manner."

Re:Visual Studio

[gabereiser]

seriously? Now I admit that Visual Studio is feature rich, only on windows, only with microsoft stacks, and doesn't compile things in a normal fashion (see #pragma) this above comment just oozes microsoft troll...

Microsoft Foundation Classes

[Latent Heat]

Yeah, yeah, reinventing LISP.

Forget that, will this be reinventing, dunno, "MFC .NET", where software is effortlessly implemented, tested, and documented using a mix of object classes, C++ templates, custom extensions to C++ that break portability, "wizard" (i.e. obscure template) generated code, a virtual machine, and calls between "managed code" on the virtual machine and native code that break security and prompt stern security scoldings when your code is on a virtual drive or "network share"?

Re:Visual Studio

[Anonymous Coward]

Visual Studio is by far the best debugger in the industry, and one of the reasons I've decided to stay out of Windows development from now on. It attracts crowds of people who rely extensively on code wizards and the debugger for all phases of development including initial coding, and if you're on that team you'll be stuck maintaining their code.

Torvalds has said some characteristically blunt words on the subject of relying on the debugger for development (not Visual Studio per se). I don't think I'd go that far.

Re:Visual Studio

[neminem]

Apparently you're a troll? A weird one, because I kind of agree with you (except about Express: yes, it's free, but it's also so limited as to be basically crap.) VS *is* really the greatest IDE I've ever used. It's not perfect, but it is the best I've used. I obviously have not used every IDE ever, and I will also admit that it's much better at debugging .net code than unmanaged c++ code, but still. Microsoft has pushed a lot of crappy, worthless software, but VS 2008 was quality, and 2010 even better (apart from a couple minor UI mistakes, easily fixable with free extensions). Notably, at least far as the summary went, it's done everything this guy is claiming he invented, since basically forever. (Though I personally leave the "recompile on the fly" option turned off; I think it's more trouble than it's worth.)

Re:Live Syntax checking.

[CastrTroy]

Welcome to VB.Net. It's been there for ages. Mind you you have to pause the debugger to edit the code, but that's probably a good idea anyway. VB.Net also has some of the best pre-compile (it has a background compiler) syntax checking of any language I've ever seen. The only time you actually have to compile the program is when you want to run it, you never have to compile to make changes show up for auto-complete. And once you're running in the debugger you can edit the code anytime the code is stopped. There's a few limitations. I'm not sure if you can add a whole class while it's running, but you can definitely fix all those little off-by-one errors and continue running the program.

Re:Visual Studio

[TechyImmigrant]

>What are the better alternatives?

Instrumented code.
Unit testing.
Live testing.
Rapid build - test turnaround.

If you're looking for a better debugger, you're doing it wrong.
You need to instrument your code with the features to make it testable from within the running code base.