Learning Golang. Day 6

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As I sat down to continue working through https://go.dev/tour/[the Go Tour], today, I felt that this week, I’d take things slightly slower, and learn more about fewer things. While last week was great, and I worked through quite a number of concepts, I felt that I was starting to gloss over things.

Because of that I felt that I’d progressively know a little bit about a broad range of things, without ever really having a deep knowledge of the language. Extrapolating this out a year or so, I felt that this would, ultimately do me a disservice.

So, today, I took time to appreciate https://go.dev/tour/moretypes/19[maps], what they are, how they can be manipulated. If you’re not familiar, https://go.dev/tour/moretypes/19[quoting the Go Tour]:

A map maps keys to values.

They’re rather like https://www.php.net/manual/en/language.types.array.php[associative arrays in PHP] and https://docs.python.org/3/tutorial/datastructures.html#dictionaries[Dictionaries in Python], if you’re familiar with those languages. Take the following PHP example.

[source,php]

'Albury', 'ADX' => 'RAF Leuchars', ]; foreach ($airportCodes as $airportCode => $airportName) { printf("%s -> %s\n", $airportCode, $airportName); } ---- The code declares a variable named `$airportCodes` which is an array string keys that map to string values. The array's key is the 3-char airport code and the array's value is the airport's full name. After that, it uses a foreach loop to iterate over and print out the airport codes and names with `printf`. Now, in the example below, you can see how `$airportCodes` could be defined and iterated over in Go. [source,go] ---- airportCodes := make(map[string]string) airportCodes["ABX"] = "Albury" airportCodes["ADX"] = "RAF Leuchars" for code, name := range airportCodes { fmt.Printf("%s -> %s\n", code, name) } ---- The `make` function is used to define a map with a string key that has a string value. Then, two entries are added, with the same key and value as in the PHP example. After that, https://gobyexample.com/range[range] is used to retrieve the airport code and name in the for loop and use `fmt.Printf` (with the same format string) to print them out. Given the similarity in concept and practice, I've been able to learn the concept quite quickly and suspect that given https://go.dev/tour/moretypes/22[the seeming simplicity of mutating maps], that I'll come to love them quite quickly. After having a play around with maps for about 15 minutes, I used the remaining 15 minutes to work through https://go.dev/tour/moretypes/23[the maps exercise], which you can see below. I don't know that it's the most elegant of solutions, but when running it, I always received `PASS` in the console output. Have a look and let me know in the comments what you think. [source,go] ---- package main import ( "golang.org/x/tour/wc" "strings" ) func WordCount(s string) map[string]int { count := make(map[string]int) for _, string := range strings.Fields(s) { count[string] = updateCount(count, string) } return count } func updateCount(count map[string]int, string string) int { if _, ok := count[string]; ok { return count[string] + 1 } return 1 } func main() { wc.Test(WordCount) } ---- I'm not sure if I'll push on with the Go Tour, tomorrow, or just play with maps a bit longer. They're fun and remind me a lot of PHP, so I might just play with them for a second session. **See you, link:/learning-golang/day-7[next time]!**