Introduction

There is plenty of meterials such as talks, tutorials and posts talking about Go, but I want to give my opinion about what I think are the strenghts and weaknesses of Go.

Full disclosure: I do not use Go at work. I use Go in my personal projects. Therefore, take my opinions with a grain of salt.

Pros

Go is one of the best programming languages I have seen in my whole life. I think that because of the following characteristics.

Standard library

If you ever asked me “Which programming language has the best and more complete standard library?” before trying Go I would have answered Python. Nowadays, I would answer Go has the best and more complete standard library.

To back up my statement that Go has the best and more complete standard library:

• It has a library for encoders and a library for decoders. They contain encoders and decoders for formats such as json, xml, csv, base64, hex, etc.
• It has a compress library that contains the following formats bzip2, flate, gzip, lzw and zlib.
• It has a crypto library with algorithms such as aes, dsa, md5, rc4, rsa, sha1, sha256, sha512, etc.
• It has a database library that contains a generic interface for SQL. It does not contain specific drivers, but it defines a common interface for all of them. Therefore, changing the backend will be pretty simple.
• It has a go library that contains all the required dependencies in order to format, parse and build any valid Go source code. It contains modules such as ast, build, doc, format, parser, token, types, etc.
• It has an image library that can handle formats such as gif, jpeg and png.
• It has a math library that has a big module to handle arbitrary-precision arithmetic.
• It has a net library that contains modules such as http, mail, smtp and url.
• It has a library for run-time reflexion called reflect.
• It has a testing library to perform the unit testing.

Obviously that is no the only content of the standard library, but these were the packages that I found to be the more interesting.

Unit test and benchmarking

I really love the idea of the compiler of the language having the ability to run the unit testing and the benchmarking in such a simple way.

To run all the unit test you just have to do the following:

go test

You can also run the unit test from a specific file with:

go test file.go

To run all the unit test that match a provided pattern you can do the following:

go test -run "Pattern*"

To perform the benchmarking of the unit test you have to do the following:

go test -bench=.

Finally, you can limit the amount of time the benchmark is running:

go test -bench=. -benchtime=20s

Channels

This is one of the big features of Go. If you ever used a Unix system, this feature will remind you of pipes. This is because a channel is used to send data between a reader and a writer (usually Goroutines).

There is plenty of good documentation about channels in Go by Example and in A Tour of Go. So, there is no need for me to write examples.

Cons

Not everything is perfect in Go. There are some perks that once they are fixed will make Go an even better programming language.

Build system

One of the main flaws of Go is the lack of a standard build system. I can understand that older languages such as C or C++ do not have a standard build system. Newer languages usually have a build system, not always from the beginning, such as Python or the more recent Rust.

Getting a standard build system for Go would be a great advantage. Maybe for Go 2.0.

Different versions of the compiler

This issue is not my biggest concern, but it is something that could be problematic for some people. The main problem is having to change the environment variables $GOROOT and $GOPATH. In Python, I can choose to use Python2 or Python3 calling different executables. The same for C and C++, I can call different versions of the compiler because they can coexist in the filesystem.

Other

In this section I talk about some features of Go that are both a Pro and a Con.

Runtime

Since I come from a systems programming background, I find hard to like a programming language that has a runtime. Unless such programming language brings more to the table to compensate for the runtime, I will try to avoid using it.

Go is one of the few languages that actually brings cool features in its runtime like detection of concurrency problems such as deadlocks.

Generics

The lack of generics in the Go language may make some people doubt the usefulness of the language, however, I do not mind not having generics. It could be because I have not yet created a big project using Go, so I have not needed them.

Maybe in Go 2.0 they will introduce some feature to address this perk. Nevertheless, I am not confident using this argument against Go. I have used C for long time and I never felt the need for generics. Therefore, I can live with a language that does not have them.

Goroutines

This is another of the big features of Go and some people will be surprised of it not being a Pro in this post. Don’t get me wrong, I think Goroutines are awesome, but you need the runtime to make them work.

That is because Goroutines do not use the thread system provided by the operating system. It uses its own implementation of thread. And all that dependency, locality, lifetime, etc. of the thread is handled by the runtime.

Conclusion

I think Go is already a great language, even with the small Cons I talk about in this post. Once the people in charge of the language fix this perks, Go will become an even better language. Go is a mature language with an awesome standard library and great tools. I will not be surprised if Go starts replacing Python in some niches even before Go gets a standard build system.