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Go Replace - simple and fast search and replace tool for command line

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Re: Go Replace - simple and fast search and replace tool for command line

#51

Post by peterwwillis »

gladimdim wrote: post #14
JoeAcchino wrote: post #13

find ~/my/docs/ -type f -name '*.txt' -exec sed -i.bak 's/inheritance/composition/g' {} + This will search all files ending in `.txt` and will exec `sed 's/inheritance/composition/g'` on it. Sed modifies files in-place and saves a backup file with .bak extension (-i.bak) and is called the minimum necessary times (-exec +). My best advice to someone using the command line is to learn `find` + `xargs` or, even better,…

Compare with "gr what-is-it -r here-you-go". I do not have to remember all that argument hell.

A C wrapper around `sed -e "s/what-is-it/here-you-go/" would be a little more efficient, and a lot simpler. Reinventing the wheel is bad for X+Y+Z reasons, where X, Y and Z are the bugs, options, and features in the last wheel.

Re: Go Replace - simple and fast search and replace tool for command line

#52

Post by andreypopp »

piranha wrote: post #38
anonymouz wrote: post #30

Earlier quoted context omitted.

Well, one can write an one-line shell alias (or script) instead of reinventing the wheel by rewriting the whole thing anew in Go. (Which is certainly good as learning experience for Go, but the end result is easier to achieve with the shell)

When you start adding coloring, nice output, .hg/.gitignore support, it becomes just a big mess. Been there, done that.

coloring is already supported by grep, .hg/.gitignore support is just a few lines

Re: Go Replace - simple and fast search and replace tool for command line

#53

Post by genwin »

artagnon wrote: post #45
piranha wrote: post #27

Earlier quoted context omitted.

> your inconsistent error passing has me somewhat confused. That was my first somewhat big program in Go plus coming from Python made a bit of hustle here. I still believe exceptions to be much better than this error-returning. :\ Never learned to do it nicely. :\ > Overall, I'd say Go is an effective language. But not beautiful, or novel in the slightest. Yes, this is more or less my feelings nowadays. It's good for…

On C. C has been around for _much_ longer than Go, and a lot of people understand C inside out. The C ecosystem is fantastic: there are extremely good implementations of virtually everything that you can use to build a production-grade application. On Go. It'll take time for a programmer to fully understand how to use a new language, and it'll be a long time before great implementations appear. If the language isn't…

In the respect of existing C programmers, maybe. Having myself never mastered C because of its complexity, in a few months part-time effort starting from getting a book on Go I built a sophisticated website. In the respect of non-C programmers, Go is extremely useful.

Re: Go Replace - simple and fast search and replace tool for command line

#54

Post by piranha »

andreypopp wrote: post #52
piranha wrote: post #38

Earlier quoted context omitted.

When you start adding coloring, nice output, .hg/.gitignore support, it becomes just a big mess. Been there, done that.

coloring is already supported by grep, .hg/.gitignore support is just a few lines

Just do it then.

Re: Go Replace - simple and fast search and replace tool for command line

#55

Post by agentultra »

genwin wrote: post #53
artagnon wrote: post #45

Earlier quoted context omitted.

On C. C has been around for _much_ longer than Go, and a lot of people understand C inside out. The C ecosystem is fantastic: there are extremely good implementations of virtually everything that you can use to build a production-grade application. On Go. It'll take time for a programmer to fully understand how to use a new language, and it'll be a long time before great implementations appear. If the language isn't…

In the respect of existing C programmers, maybe. Having myself never mastered C because of its complexity, in a few months part-time effort starting from getting a book on Go I built a sophisticated website. In the respect of non-C programmers, Go is extremely useful.

C isn't any more difficult to understand, IMO. Obviously Go has the advantage of hindsight and an opportunity to go back on the trade-offs that were made for compiler efficiency before C was standardized. However, at it's core I think C is much more simple than Go and theoretically should be easier to understand.

I find GC to be a useful tool but have you ever looked into the implementation of one? Or have you run into a situation where it was necessary to reason about the performance characteristics of a GC in relation to some algorithm or tight main loop?

I don't find C's lack of GC any more complex than GC. In fact I find it much more simple. It requires more discipline on the part of the programmer (and perhaps that is where the appeal of a GC comes from). Perhaps it's because I started programming with addressing memory and building up a mental model of how it works and have only encountered GC as a useful addition to my programming toolbox (instead of an always-present assumption).

As well, co-routine trampolining (which is what I assume the playful pun go-routines are referring to... please correct me if I am wrong) isn't a very "simple" thing to understand either. At least they are not any more simple than threads so I don't understand how they make learning Go any more easy for non-C programmers (except perhaps exposure to co-routines in a language that already has them like Python).

I guess what I am saying is that you could have just as easily mastered as much C in those few months as you did Go.

Re: Go Replace - simple and fast search and replace tool for command line

#56

Post by to3m »

agentultra wrote: post #55
genwin wrote: post #53

Earlier quoted context omitted.

In the respect of existing C programmers, maybe. Having myself never mastered C because of its complexity, in a few months part-time effort starting from getting a book on Go I built a sophisticated website. In the respect of non-C programmers, Go is extremely useful.

C isn't any more difficult to understand, IMO. Obviously Go has the advantage of hindsight and an opportunity to go back on the trade-offs that were made for compiler efficiency before C was standardized. However, at it's core I think C is much more simple than Go and theoretically should be easier to understand. I find GC to be a useful tool but have you ever looked into the implementation of one? Or have you run in…

I believe the goroutines are cooperative, yielded either explicitly or by calling various library functions. So you don't need quite the same sort of locking as you do with preemptively-multitasked threads, and there's also a much larger set of atomic operations. This should make things much easier...

Re: Go Replace - simple and fast search and replace tool for command line

#57

Post by to3m »

swah wrote: post #25
piranha wrote: post #23

Earlier quoted context omitted.

Should be fixed, can you download new version please?

Working! Do you use colors? They don't work the same in DOS, I believe. I'm seeing some escape sequences. ←[0;32;49mRS\terms.tex ←[0m←[1;39;49m←[0;33;49m25:←[0m ←[0;39;43mOEM←[0m & \\ \hline

It's been a while but those look like ANSI escapes so I think if you add something like DEVICEHIGH=C:\DOS\ANSI.SYS to your CONFIG.SYS then you should find it starts to interpret them correctly. I think ANSI.SYS uses up less than 30K.

Re: Go Replace - simple and fast search and replace tool for command line

#58

Post by genwin »

agentultra wrote: post #55
genwin wrote: post #53

Earlier quoted context omitted.

In the respect of existing C programmers, maybe. Having myself never mastered C because of its complexity, in a few months part-time effort starting from getting a book on Go I built a sophisticated website. In the respect of non-C programmers, Go is extremely useful.

C isn't any more difficult to understand, IMO. Obviously Go has the advantage of hindsight and an opportunity to go back on the trade-offs that were made for compiler efficiency before C was standardized. However, at it's core I think C is much more simple than Go and theoretically should be easier to understand. I find GC to be a useful tool but have you ever looked into the implementation of one? Or have you run in…

I think some people's intellects are more suited to learning and mastering C, which is great for the development of major products. For general business applications development and websites I think C may be overkill compared to Go. In a test of 2K concurrent users hitting my website on a cheap box, each served a unique page, all users are served fast, so I'm glad that Go is handling GC instead of me. I've done multi-threaded code in C# and find goroutines much simpler.

I have goroutines referencing objects created in other goroutines. It seems to do my own GC without becoming too unwieldy I'd have to write something like the generic GC code Go already has built-in. It was nice to not have to think about that at all and still get great performance.

Re: Go Replace - simple and fast search and replace tool for command line

#59

Post by artagnon »

agentultra wrote: post #55
genwin wrote: post #53

Earlier quoted context omitted.

In the respect of existing C programmers, maybe. Having myself never mastered C because of its complexity, in a few months part-time effort starting from getting a book on Go I built a sophisticated website. In the respect of non-C programmers, Go is extremely useful.

C isn't any more difficult to understand, IMO. Obviously Go has the advantage of hindsight and an opportunity to go back on the trade-offs that were made for compiler efficiency before C was standardized. However, at it's core I think C is much more simple than Go and theoretically should be easier to understand. I find GC to be a useful tool but have you ever looked into the implementation of one? Or have you run in…

I would argue that C is probably the easiest language to understand, if you know the basics of hardware. C is essentially portable assembly. The C standard is tiny, and the behaviors are very clearly defined. The challenge is not in understanding the language, but rather in honing the engineering discipline required to use it to write real-world programs.

It lacks a garbage collector because there was no concept of garbage collector when the language was created. A C program does not provide enough information for a good garbage collector: the best we can do is a conservative garbage collector, Boehm. The garbage collector adds to the running-cost to the program for the promise of automatic memory management. While the GC might run concurrently, any sort of relocation (for compacting) will require it to pause the entire program: these GC pauses can be fatal if your program is the Linux kernel or some high-frequency trading application. Even otherwise, it is important to remember that every GC introduces trade-offs; the "freedom" from manual memory management is only worth it if your GC is good.

When I'm not writing C, I like writing Ruby. I like that it's a beautiful evolving language packed with features. And for the little applications I'm writing, I don't care even if it takes a second longer. I like that I'm not being verbose about anything, and not manually managing memory. Writing something like Jekyll in C would be an absolute pain in the arse, and totally not worth it. Obviously, the lesson is: use the right tool for the right job.

The pthreads API can certainly be very intimidating, and it requires a lot of practice to master threading in C. I like that Go has taken the concept of coroutines from Lisp (Scheme's call/cc) and turned it into something called Gorountines in imperative land. Although it's nothing novel, I won't deny that it's a nice abstraction to work with while doing multi-threaded programming.

If we were to redo C from scratch today, I'd definitely bake in more safety features. Probably design a close garbage collected dialect. For better or worse, that's an entirely theoretical scenario: we have Go today, but I'm not sure where exactly it fits in:

1. It obviously can't replace C in linux, git, zlib, ssh, openssl, libcurl, nginx, varnish, or anything as core.

2. Since it doesn't have generics or any higher OO features, it can't displace C++ in chrome or llvm.

3. When python, ruby, javascript are around, why will anyone want to use a strongly typed language for writing web applications? Okay, maybe some intensive web services like search.

Tools? The most popular Go repositories on GitHub are dotcloud/docker (software deployment tool), burke/zeus (Rails preloader) and ha/doozerd (a very specific kind of datastore).

Might be useful in Android development, but is everyone's stuck in a Dalvik swamp there.

Re: Go Replace - simple and fast search and replace tool for command line

#60

Post by genwin »

artagnon wrote: post #59
agentultra wrote: post #55

Earlier quoted context omitted.

C isn't any more difficult to understand, IMO. Obviously Go has the advantage of hindsight and an opportunity to go back on the trade-offs that were made for compiler efficiency before C was standardized. However, at it's core I think C is much more simple than Go and theoretically should be easier to understand. I find GC to be a useful tool but have you ever looked into the implementation of one? Or have you run in…

I would argue that C is probably the easiest language to understand, if you know the basics of hardware. C is essentially portable assembly. The C standard is tiny, and the behaviors are very clearly defined. The challenge is not in understanding the language, but rather in honing the engineering discipline required to use it to write real-world programs. It lacks a garbage collector because there was no concept of g…

> When python, ruby, javascript are around, why will anyone want to use a strongly typed language for writing web applications?

Because Go is multiples faster at runtime! After using Go I lost interest in learning Python, which seems only slightly easier to code in.

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