{"id":607,"date":"2022-05-09T09:52:00","date_gmt":"2022-05-09T09:52:00","guid":{"rendered":"https:\/\/andrejacobs.org\/?p=607"},"modified":"2022-05-27T16:04:15","modified_gmt":"2022-05-27T16:04:15","slug":"learning-go-day-12","status":"publish","type":"post","link":"https:\/\/andrejacobs.org\/study-notes\/learning-go-day-12\/","title":{"rendered":"Learning Go &#8211; Day 12"},"content":{"rendered":"\n<p class=\"has-small-font-size\">Featured image by&nbsp;<a href=\"https:\/\/github.com\/egonelbre\/gophers\" target=\"_blank\" rel=\"noreferrer noopener\">Egon Elbre<\/a><\/p>\n\n\n\n<div class=\"wp-block-jetpack-markdown\"><h2>Package dependencies<\/h2>\n<p>One of the topics that you will encounter and even try to understand in your own projects, is just how exactly to structure Go projects.<\/p>\n<p>I will be creating two new GitHub repositories in order to get a better understanding of how package imports work and just how I might open source some code later that can be used by others.<\/p>\n<p>You can find the two repositories here: <a href=\"https:\/\/github.com\/andrejacobs\/go-test1\">go-test1<\/a> and <a href=\"https:\/\/github.com\/andrejacobs\/go-test2\">go-test2<\/a><\/p>\n<ul>\n<li>Created a new repository called <code>go-test1<\/code> and cloned it locally. This will provide some code to be consumed by another repository.<\/li>\n<li>Initialized the go module.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ cd go-test1\n$ go mod init github.com\/andrejacobs\/go-test1\n<\/code><\/pre>\n<ul>\n<li>Created another new repository called <code>go-test2<\/code> and clone and set it up as well.<\/li>\n<\/ul>\n<h3>Package 1 &#8211; Simple quote generator<\/h3>\n<ul>\n<li><code>go-test1<\/code> is going to be a simple random quote generator.\n<ul>\n<li>Package <code>quote<\/code> provides a type to represent a list of quotes along with a method to generate some random quotes.<\/li>\n<li>Package <code>internal<\/code> is used by the generate.go file to generate the random people and quote lines. Also this was a great test to see how Go handles the special <code>internal<\/code> package importing.<\/li>\n<li>The repository also supplies a CLI to generate random quotes.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ tree\n.\n\u251c\u2500\u2500 LICENSE\n\u251c\u2500\u2500 README.md\n\u251c\u2500\u2500 cmd\n\u2502\u00a0\u00a0 \u2514\u2500\u2500 quote-cli\n\u2502\u00a0\u00a0     \u2514\u2500\u2500 main.go\n\u251c\u2500\u2500 go.mod\n\u251c\u2500\u2500 internal\n\u2502\u00a0\u00a0 \u2514\u2500\u2500 random.go\n\u2514\u2500\u2500 quote\n    \u251c\u2500\u2500 generate.go\n    \u251c\u2500\u2500 generate_test.go\n    \u251c\u2500\u2500 list.go\n    \u2514\u2500\u2500 list_test.go\n\n4 directories, 9 files\n<\/code><\/pre>\n<ul>\n<li>quote\/list.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package quote\n\ntype Quote struct {\n\tLine string\n\tWho  string\n}\n\ntype QuoteList struct {\n\tQuotes []Quote\n}\n\nfunc (ql *QuoteList) Add(who string, line string) {\n\tq := Quote{\n\t\tWho:  who,\n\t\tLine: line,\n\t}\n\n\tql.Quotes = append(ql.Quotes, q)\n}\n<\/code><\/pre>\n<ul>\n<li>quote\/list_test.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package quote_test\n\nimport (\n\t&quot;testing&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test1\/quote&quot;\n)\n\nfunc TestListAdd(t *testing.T) {\n\tql := &amp;quote.QuoteList{}\n\n\tif len(ql.Quotes) &gt; 0 {\n\t\tt.Fatal(&quot;QuoteList not initialized correctly&quot;)\n\t}\n\n\tql.Add(&quot;Person 1&quot;, &quot;The quick brown fox&quot;)\n\tql.Add(&quot;Person 2&quot;, &quot;Jumped over the lazy dog&quot;)\n\n\tif len(ql.Quotes) != 2 {\n\t\tt.Fatalf(&quot;Expected 2 quotes in the list, instead there were: %d&quot;, len(ql.Quotes))\n\t}\n}\n<\/code><\/pre>\n<ul>\n<li>quote\/generate.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package quote\n\nimport (\n\t&quot;github.com\/andrejacobs\/go-test1\/internal&quot;\n)\n\nfunc (ql *QuoteList) Generate(count int) {\n\n\tfor i := 0; i &lt; count; i++ {\n\t\tperson := internal.RandomPerson()\n\t\tline := internal.RandomLine()\n\t\tql.Add(person, line)\n\t}\n}\n<\/code><\/pre>\n<ul>\n<li>quote\/generate_test.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package quote_test\n\nimport (\n\t&quot;testing&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test1\/quote&quot;\n)\n\nfunc TestGenerate(t *testing.T) {\n\tql := &amp;quote.QuoteList{}\n\n\texpectedCount := 5\n\tql.Generate(expectedCount)\n\tif len(ql.Quotes) != expectedCount {\n\t\tt.Fatalf(&quot;Expected %d quotes to be generated, instead we got %d&quot;, expectedCount, len(ql.Quotes))\n\t}\n}\n<\/code><\/pre>\n<ul>\n<li>internal\/random.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package internal\n\nimport &quot;math\/rand&quot;\n\nfunc RandomPerson() string {\n\tvar people = []string{\n\t\t&quot;Jannie&quot;,\n\t\t&quot;Sannie&quot;,\n\t\t&quot;Pieter&quot;,\n\t\t&quot;Stephan&quot;,\n\t\t&quot;Kobus&quot;,\n\t}\n\n\tperson := people[rand.Intn(len(people))]\n\treturn person\n}\n\nfunc RandomLine() string {\n\tvar lines = []string{\n\t\t&quot;Lorem ipsum dolor sit amet, consectetur adipiscing elit.&quot;,\n\t\t&quot;Mauris at metus in lectus cursus placerat.&quot;,\n\t\t&quot;Quisque gravida mauris vel ante luctus, eget congue est ornare.&quot;,\n\t\t&quot;Sed semper mauris nec commodo pharetra.&quot;,\n\t\t&quot;Fusce nec elit sagittis, sodales nulla a, vehicula libero.&quot;,\n\t\t&quot;Mauris dignissim libero nec neque tristique, nec fringilla nunc pretium.&quot;,\n\t\t&quot;Maecenas fermentum diam eget justo euismod bibendum.&quot;,\n\t\t&quot;Nam euismod sapien vitae quam dapibus molestie.&quot;,\n\t\t&quot;Sed ac ligula eget ipsum semper pharetra.&quot;,\n\t\t&quot;Morbi vestibulum augue quis nulla pharetra, at finibus leo consectetur.&quot;,\n\t}\n\n\tline := lines[rand.Intn(len(lines))]\n\treturn line\n}\n<\/code><\/pre>\n<ul>\n<li>cmd\/quote-cli\/main.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package main\n\nimport (\n\t&quot;flag&quot;\n\t&quot;fmt&quot;\n\t&quot;io&quot;\n\t&quot;os&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test1\/quote&quot;\n)\n\nfunc main() {\n\tcountFlag := flag.Int(&quot;count&quot;, 1, &quot;The number of quotes to print on STDOUT&quot;)\n\tflag.Parse()\n\n\tif err := run(os.Stdout, *countFlag); err != nil {\n\t\tfmt.Fprintln(os.Stderr, err)\n\t\tos.Exit(1)\n\t}\n}\n\nfunc run(out io.Writer, count int) error {\n\tql := &amp;quote.QuoteList{}\n\tql.Generate(count)\n\n\tfor _, quote := range ql.Quotes {\n\t\t_, err := fmt.Fprintf(out, &quot;%q - %s\\n&quot;, quote.Line, quote.Who)\n\t\tif err != nil {\n\t\t\treturn err\n\t\t}\n\t}\n\n\treturn nil\n}\n<\/code><\/pre>\n<ul>\n<li>Run unit-test<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ cd quote\n$ go test -v\n=== RUN   TestGenerate\n--- PASS: TestGenerate (0.00s)\n=== RUN   TestListAdd\n--- PASS: TestListAdd (0.00s)\nPASS\nok      github.com\/andrejacobs\/go-test1\/quote   0.225s\n<\/code><\/pre>\n<ul>\n<li>Run the CLI.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ cd cmd\/quote-cli\n$ go run .\n&quot;Nam euismod sapien vitae quam dapibus molestie.&quot; - Sannie\n\n$ go run . -count 5\n&quot;Nam euismod sapien vitae quam dapibus molestie.&quot; - Sannie\n&quot;Morbi vestibulum augue quis nulla pharetra, at finibus leo consectetur.&quot; - Pieter\n&quot;Sed ac ligula eget ipsum semper pharetra.&quot; - Sannie\n&quot;Lorem ipsum dolor sit amet, consectetur adipiscing elit.&quot; - Jannie\n&quot;Lorem ipsum dolor sit amet, consectetur adipiscing elit.&quot; - Sannie\n<\/code><\/pre>\n<h3>Package 2 &#8211; Sorted quote generator<\/h3>\n<ul>\n<li><code>go-test2<\/code> is going to use <code>go-test1<\/code> to generate random quotes and extend it by adding the ability to have the quotes sorted alphabetically.<\/li>\n<li>Add dependency on <code>go-test1<\/code> by using <code>go get<\/code><\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ go get -u -x github.com\/andrejacobs\/go-test1@latest\n...\ngo: downloading github.com\/andrejacobs\/go-test1 v0.0.0-20220509114742-d186c44a2d88\n<\/code><\/pre>\n<p><strong>HANDY TIP:<\/strong> You can pass <code>-x<\/code> to <code>go get<\/code> so that it prints out all the commands being run. This is handy for debugging why git or ssh is failing.<\/p>\n<ul>\n<li>The package have been made available at <code>$(go env GOPATH)\/pkg\/mod\/github.com\/andrejacobs\/go-test1@v0.0.0-20220509114742-d186c44a2d88<\/code><\/li>\n<li>The dependency has been added to go.mod for go-test2.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ cat go.mod\nmodule github.com\/andrejacobs\/go-test2\n\ngo 1.18\n\nrequire github.com\/andrejacobs\/go-test1 v0.0.0-20220509114742-d186c44a2d88 \/\/ indirect\n<\/code><\/pre>\n<ul>\n<li>NOTE: That the entire git repository for go-test1 was cloned. This is still the case even if you tried to just fetch the specific package. For example if you \u201cgo get &#8230; go-test1\/quote@latest\u201d.<\/li>\n<li>This is the structure I will be using.\n<ul>\n<li>Package <code>sorted<\/code> will provide a new sorted QuoteList that wraps the quote.QuoteList type from go-test1 module.<\/li>\n<li>There is also a CLI under cmd\/sorted-quote-cli.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ tree\n.\n\u251c\u2500\u2500 LICENSE\n\u251c\u2500\u2500 README.md\n\u251c\u2500\u2500 cmd\n\u2502\u00a0\u00a0 \u2514\u2500\u2500 sorted-quote-cli\n\u2502\u00a0\u00a0     \u2514\u2500\u2500 main.go\n\u251c\u2500\u2500 go.mod\n\u251c\u2500\u2500 go.sum\n\u2514\u2500\u2500 sorted\n    \u251c\u2500\u2500 quoteList.go\n    \u2514\u2500\u2500 sort_test.go\n\n3 directories, 7 files\n<\/code><\/pre>\n<ul>\n<li>sorted\/quoteList.go\n<ul>\n<li><strong>NOTE:<\/strong> One big thing I learned through this exercise is that you can\u2019t add methods to a type that is outside of the package. I.e. you can\u2019t just extend like you can in Swift. However what you can do is, to wrap the existing type inside your own package and then add methods to that type. Like what I have done with QuoteList below.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package sorted\n\nimport (\n\t&quot;sort&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test1\/quote&quot;\n)\n\ntype QuoteList struct {\n\tquote.QuoteList\n}\n\nfunc (ql *QuoteList) Sort() {\n\tsort.SliceStable(ql.Quotes, func(i, j int) bool {\n\t\treturn ql.Quotes[i].Line &lt; ql.Quotes[j].Line\n\t})\n}\n\nfunc (ql *QuoteList) Add(who string, line string) {\n\tql.QuoteList.Add(who, line)\n\tql.Sort()\n}\n<\/code><\/pre>\n<ul>\n<li>sorted\/sort_test.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package sorted_test\n\nimport (\n\t&quot;testing&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test2\/sorted&quot;\n)\n\nfunc TestSort(t *testing.T) {\n\tql := &amp;sorted.QuoteList{}\n\n\tql.Add(&quot;p1&quot;, &quot;Bravo&quot;)\n\tql.Add(&quot;p2&quot;, &quot;Zebra&quot;)\n\tql.Add(&quot;p3&quot;, &quot;Alpha&quot;)\n\n\tif ql.Quotes[0].Line != &quot;Alpha&quot; &amp;&amp;\n\t\tql.Quotes[1].Line != &quot;Bravo&quot; &amp;&amp;\n\t\tql.Quotes[2].Line != &quot;Zebra&quot; {\n\t\tt.Fatal(&quot;Expected the quotes to be sorted&quot;)\n\t}\n}\n<\/code><\/pre>\n<ul>\n<li>cmd\/sorted-quote-cli\/main.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package main\n\nimport (\n\t&quot;flag&quot;\n\t&quot;fmt&quot;\n\t&quot;io&quot;\n\t&quot;os&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test2\/sorted&quot;\n)\n\nfunc main() {\n\tcountFlag := flag.Int(&quot;count&quot;, 1, &quot;The number of quotes to print on STDOUT&quot;)\n\tflag.Parse()\n\n\tif err := run(os.Stdout, *countFlag); err != nil {\n\t\tfmt.Fprintln(os.Stderr, err)\n\t\tos.Exit(1)\n\t}\n}\n\nfunc run(out io.Writer, count int) error {\n\tql := &amp;sorted.QuoteList{}\n\tql.Generate(count)\n\tql.Sort()\n\n\tfor _, quote := range ql.Quotes {\n\t\t_, err := fmt.Fprintf(out, &quot;%q - %s\\n&quot;, quote.Line, quote.Who)\n\t\tif err != nil {\n\t\t\treturn err\n\t\t}\n\t}\n\n\treturn nil\n}\n<\/code><\/pre>\n<ul>\n<li>Run unit-tests.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ cd sorted\n$ go test -v\n=== RUN   TestSort\n--- PASS: TestSort (0.00s)\nPASS\nok      github.com\/andrejacobs\/go-test2\/sorted  0.185s\n<\/code><\/pre>\n<ul>\n<li>Run the CLI.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ cd cmd\/sorted-quote-cli\n$ go run . -count 5\n&quot;Lorem ipsum dolor sit amet, consectetur adipiscing elit.&quot; - Jannie\n&quot;Lorem ipsum dolor sit amet, consectetur adipiscing elit.&quot; - Sannie\n&quot;Morbi vestibulum augue quis nulla pharetra, at finibus leo consectetur.&quot; - Pieter\n&quot;Nam euismod sapien vitae quam dapibus molestie.&quot; - Sannie\n&quot;Sed ac ligula eget ipsum semper pharetra.&quot; - Sannie\n<\/code><\/pre>\n<h3>Versioning<\/h3>\n<p>Now that I have two working packages in two different git repositories it is time to add functionality to go-test1 and see how versioning will work. From the previous \u201cgo get\u201d we can see that version v0.0.0 was used.<\/p>\n<ul>\n<li>I will be adding a new package <code>jsonquote<\/code> that will simply be used to encode the QuoteList into JSON.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">jsonquote\n\u251c\u2500\u2500 json.go\n\u2514\u2500\u2500 json_test.go\n<\/code><\/pre>\n<ul>\n<li>jsonquote\/json.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package jsonquote\n\nimport (\n\t&quot;encoding\/json&quot;\n\t&quot;io&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test1\/quote&quot;\n)\n\nfunc Encode(out io.Writer, ql *quote.QuoteList) {\n\tencoder := json.NewEncoder(out)\n\tencoder.Encode(ql)\n}\n<\/code><\/pre>\n<ul>\n<li>jsonquote\/json_test.go<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package jsonquote_test\n\nimport (\n\t&quot;bytes&quot;\n\t&quot;testing&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test1\/jsonquote&quot;\n\t&quot;github.com\/andrejacobs\/go-test1\/quote&quot;\n)\n\nfunc TestJsonEncoding(t *testing.T) {\n\tql := &amp;quote.QuoteList{}\n\tql.Add(&quot;p1&quot;, &quot;line1&quot;)\n\tql.Add(&quot;p2&quot;, &quot;line2&quot;)\n\tql.Add(&quot;p3&quot;, &quot;line3&quot;)\n\n\tvar result bytes.Buffer\n\tjsonquote.Encode(&amp;result, ql)\n\n\texpected := &quot;{\\&quot;Quotes\\&quot;:[{\\&quot;Line\\&quot;:\\&quot;line1\\&quot;,\\&quot;Who\\&quot;:\\&quot;p1\\&quot;},{\\&quot;Line\\&quot;:\\&quot;line2\\&quot;,\\&quot;Who\\&quot;:\\&quot;p2\\&quot;},{\\&quot;Line\\&quot;:\\&quot;line3\\&quot;,\\&quot;Who\\&quot;:\\&quot;p3\\&quot;}]}\\n&quot;\n\tif result.String() != expected {\n\t\tt.Fatalf(&quot;Expected json:\\n%q\\n\\nInstead we received:\\n%q&quot;, expected, result.String())\n\t}\n}\n<\/code><\/pre>\n<ul>\n<li>Modified the CLI to include the option of encoding into JSON.<\/li>\n<\/ul>\n<pre><code class=\"language-go\">package main\n\nimport (\n\t&quot;flag&quot;\n\t&quot;fmt&quot;\n\t&quot;io&quot;\n\t&quot;os&quot;\n\n\t&quot;github.com\/andrejacobs\/go-test1\/jsonquote&quot;\n\t&quot;github.com\/andrejacobs\/go-test1\/quote&quot;\n)\n\nfunc main() {\n\tcountFlag := flag.Int(&quot;count&quot;, 1, &quot;The number of quotes to print&quot;)\n\tjsonFlag := flag.Bool(&quot;json&quot;, false, &quot;Encode the quotes in JSON&quot;)\n\tflag.Parse()\n\n\tif err := run(os.Stdout, *countFlag, *jsonFlag); err != nil {\n\t\tfmt.Fprintln(os.Stderr, err)\n\t\tos.Exit(1)\n\t}\n}\n\nfunc run(out io.Writer, count int, outputJson bool) error {\n\tql := &amp;quote.QuoteList{}\n\tql.Generate(count)\n\n\tif outputJson {\n\t\tjsonquote.Encode(out, ql)\n\t} else {\n\t\tfor _, quote := range ql.Quotes {\n\t\t\t_, err := fmt.Fprintf(out, &quot;%q - %s\\n&quot;, quote.Line, quote.Who)\n\t\t\tif err != nil {\n\t\t\t\treturn err\n\t\t\t}\n\t\t}\n\t}\n\treturn nil\n}\n<\/code><\/pre>\n<ul>\n<li>Run unit-test and the CLI.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ cd jsonquote\n$ go test -v\n=== RUN   TestJsonEncoding\n--- PASS: TestJsonEncoding (0.00s)\nPASS\nok  \tgithub.com\/andrejacobs\/go-test1\/jsonquote\t0.122s\n\n$ cd ..\/cmd\/quote-cli\n$ go run . -count 3 -json\n{&quot;Quotes&quot;:[{&quot;Line&quot;:&quot;Nam euismod sapien vitae quam dapibus molestie.&quot;,&quot;Who&quot;:&quot;Sannie&quot;},{&quot;Line&quot;:&quot;Morbi vestibulum augue quis nulla pharetra, at finibus leo consectetur.&quot;,&quot;Who&quot;:&quot;Pieter&quot;},{&quot;Line&quot;:&quot;Sed ac ligula eget ipsum semper pharetra.&quot;,&quot;Who&quot;:&quot;Sannie&quot;}]}\n<\/code><\/pre>\n<ul>\n<li>Commit the changes in git and push to origin.<\/li>\n<li>Created a v0.1.0 release in GitHub.<\/li>\n<\/ul>\n<p><strong>NOTE:<\/strong> And now the penny drops! Go doesn\u2019t seem to have consensus yet on how to do versioning and dependency management. There are a number of tools to manage versions for you and also the concept of vendoring. I will have to dig deeper into this later, for now it is safe to say you really have to consider how you structure your API.<\/p>\n<ul>\n<li>Getting latest go-test1 into go-test2 to use.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ go get -u -x github.com\/andrejacobs\/go-test1@latest\n<\/code><\/pre>\n<p><img decoding=\"async\" src=\"https:\/\/andrejacobs.org\/wp-content\/uploads\/2022\/05\/go-test1version.png\" alt=\"\"><\/p>\n<p>Notice how it still states v0.0.0, however inspecting the files in my GOPATH I can see it grabbed the latest copy from the git repo. My guess is it always grabs latest master and not actually based on the github release \/ tag.<\/p>\n<ul>\n<li>I have added the same <code>-json<\/code> argument support to go-test2\u2019s CLI and tested it.<\/li>\n<\/ul>\n<pre><code class=\"language-bash\">$ go run . -count 3 -json\n{&quot;Quotes&quot;:[{&quot;Line&quot;:&quot;Morbi vestibulum augue quis nulla pharetra, at finibus leo consectetur.&quot;,&quot;Who&quot;:&quot;Pieter&quot;},{&quot;Line&quot;:&quot;Nam euismod sapien vitae quam dapibus molestie.&quot;,&quot;Who&quot;:&quot;Sannie&quot;},{&quot;Line&quot;:&quot;Sed ac ligula eget ipsum semper pharetra.&quot;,&quot;Who&quot;:&quot;Sannie&quot;}]}\n<\/code><\/pre>\n<h3>Finishing up<\/h3>\n<p>All in all this was a very worthwhile experiment and I have learned a lot upfront about how I will be tackling my own initial applications, modules and packages.<\/p>\n<p>I certainly need to brush up a bit on what the best versioning and dependency management is for golang.<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Featured image by&nbsp;Egon Elbre [&#8230;]<\/p>\n<p><a class=\"understrap-read-more-link\" href=\"https:\/\/andrejacobs.org\/study-notes\/learning-go-day-12\/\">Read more &rarr;<\/a><\/p>\n","protected":false},"author":2,"featured_media":585,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[52],"tags":[53],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v19.13 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Learning Go - Day 12 - Andr\u00e9 Jacobs<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/andrejacobs.org\/study-notes\/learning-go-day-12\/\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Learning Go - Day 12 - Andr\u00e9 Jacobs\" \/>\n<meta property=\"og:description\" content=\"Featured image by&nbsp;Egon Elbre [...]Read more &rarr;\" \/>\n<meta property=\"og:url\" content=\"https:\/\/andrejacobs.org\/study-notes\/learning-go-day-12\/\" \/>\n<meta property=\"og:site_name\" content=\"Andr\u00e9 Jacobs\" \/>\n<meta property=\"article:published_time\" content=\"2022-05-09T09:52:00+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2022-05-27T16:04:15+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/andrejacobs.org\/wp-content\/uploads\/2022\/05\/robin-hood.png\" \/>\n\t<meta property=\"og:image:width\" content=\"490\" \/>\n\t<meta property=\"og:image:height\" content=\"654\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"author\" content=\"Andr\u00e9 Jacobs\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@andrejacobs81\" \/>\n<meta name=\"twitter:site\" content=\"@andrejacobs81\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Andr\u00e9 Jacobs\" \/>\n\t<meta name=\"twitter:label2\" content=\"Estimated reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"8 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/andrejacobs.org\/study-notes\/learning-go-day-12\/#article\",\"isPartOf\":{\"@id\":\"https:\/\/andrejacobs.org\/study-notes\/learning-go-day-12\/\"},\"author\":{\"name\":\"Andr\u00e9 Jacobs\",\"@id\":\"https:\/\/andrejacobs.org\/#\/schema\/person\/3d38360883015e883c80c2fb875c5a68\"},\"headline\":\"Learning Go &#8211; 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