A Week with Go, Day 1

Go is a general purpose systems programming language developed at Google by Robert Griesemer, Rob Pike, and Ken Thompson. Go has been on my radar since it became publicly available a year ago as an open source project, and since then its documentation has been improving and a small community of users has been forming around the language. Last week I had some time off from work that coincided nicely with the Thanksgiving holiday and I thought it'd be fun to spend some of it looking at Go. Here's the first in a series of five posts that share my thoughts and experiences of spending a week with Go.

My first Go programs were solutions to a couple Project Euler solutions. This was just to get a basic feel for its syntax.

Problem 1

package main

import fmt "fmt"

func main() {
    sum := 0
    for i := 0; i < 1000; i++ {
        if i%3 == 0 || i%5 == 0 {
            sum += i
        }
    }
    fmt.Printf("%d\n", sum)
}

There are a few oddities, but overall there's nothing earth shattering with Go's syntax.

• Parentheses aren't used in constructs like if and for as they are in C, though braces are always required, and semicolons are used as separators-- not terminators. The resulting code looks nice and clean. The lack of terminators is a bit disconcerting, though... have we learned nothing from JavaScript?
• := elides variable declarations and the compiler will deduce the variable's type, reminiscent of OCaml's type inference (though it doesn't extend to function declarations and the like). The more verbose way of declaring and assigning sum would be var sum int = 0. It's nice once you get the hang of it, but I think this might be a bit confusing for new programmers.

Problem 2

package main

import fmt "fmt"

func main() {
    a, b, c, sum := 0, 1, 0, 0
    for c < 4000000 {
        c = a + b
        a, b = b, c

        if c%2 == 0 {
            sum += c
        }
    }

    fmt.Printf("%d\n", sum)
}

Whoa, Go doesn't have a while loop? Surely this is madness!

• The designers extended the minimal syntax philosophy to common language constructs as well. Different for variations are used to write not only your traditional for loops, but also while loops and foreach/for in loops. I think for c < 4000000 is a bit awkward to read but it becomes second nature to write in short order.

It's nice to have less keywords and the code looks clean and readable. Despite some hesitance, my opinion was favorable overall after the first day.

Feel free to share your impressions of Go in the comments below and come back tomorrow for day 2.