Struct in Golang // Go's _structs_ are typed collections of fields. 0 was released at 2012. Notes from "A Tour of Go" If you already installed Go then you can run an interactive tour of Go locally: go tool tour (This code probably won't compile). I am using a yaml parser to parse the files but my question is how in Golang I can build struct that when I parse the doc it will automatically fill the main struct and will include the sub structs (such as dependency/ install sections ) The code which done the parse and working is the following:. Golang Cheat Sheet. The latest Tweets from Golangbot (@bot_golang). Go Cheat Sheet Credits Most example code taken from A Tour of Go, which is an excellent introduction to Go. We can take this example one step further and create a website using a slice of blog posts :). Eg: arr[0:5] will give a slice of first 5 elements of an array. added possibility to make slice or map of dynamic structs added. Slice values are deeply equal when all of the following are true: they are both nil or both non-nil, they have the same length, and either they point to the same initial entry of the same underlying array (that is, &x == &y) or their corresponding elements (up to length) are deeply equal. Golang has the ability to declare and create own data types by combining one or more types, including both built-in and user-defined types. Merging slices. Andrew Gerrand 5 January 2011 Introduction. Slice is an essential component of Go programming language. The default zero value of a struct has all its fields zeroed. In general DeepEqual is a recursive relaxation of Go's == operator. A slice, on the other hand, is a dynamically-sized, flexible view into the elements of an array. Appending and prepending golang slices. A slice is a segment of dynamic arrays that can grow and shrink as you see fit. An easier approach would be changing the Tags field of the Task struct to string and do this conversion somewhere in the application code before persisting the task. I am using a yaml parser to parse the files but my question is how in Golang I can build struct that when I parse the doc it will automatically fill the main struct and will include the sub structs (such as dependency/ install sections ) The code which done the parse and working is the following:. No arrays, no slices of structs, etc. They're useful for grouping data together to form records. With array and slices, it returns the index of the item as integer. Ten Reasons Why I Don't Like Golang. It defines a collection of "fields", each field is a name and a value of a specific type. プログラミング言語Go Tour ( Go言語基礎文法最速マスター) へようこそ!. Golang has gained tremendous grounds in Software development in few years of its launch. A slice, on the other hand, is a dynamically-sized, flexible view into the elements of an array. []byte has two lengths: the current length of the data and the capacity. In general DeepEqual is a recursive relaxation of Go's == operator. If the nature of the struct is something that can be changed, even if it never is in your program, it is not a primitive data value and should be implemented to be shared with a pointer. Shelled-out Commands In Golang 29 Dec 2014. GoLang Slice of Structs. In general, carefully selected data structure can bring higher operation or storage efficiency. [see Golang: Array] Syntax of Slice Type []type → syntax for the type of slice with each slot of type type. GoLang Array vs Slice - 17 Slice Examples in Go Programming Language. a line number in the source code). Slices help in this regard. I wanted to go from existing Go structs, which used all the features of Go, to a marshaler, an unmarshaler, and a. Let’s get similar output again, but using a loop which will give an indication how interfaces can produce cleaner, simpler, and more scalable code. Run code here: GoPlayground. However, I should ask, what are you trying to do? However, I should ask, what are you trying to do? -Gyepi -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. Let's define the website struct first. So they may not think of it as an array as much as a repeat occurence of a key. How to Parse JSON in Golang (With Examples) October 18, 2017 (Updated on June 26, 2019) In this post, we will learn how to work with JSON in Go, in the simplest way possible. Reference contiguous portion of an array; Referencing a slice by its variable name references the entire slice. slice作为函数参数时是引用传递。. Garbage collection is a convenient feature of Go - automatic memory management makes code cleaner and memory leaks less likely. The slice is … Rahul Raut GoLang cap / GoLang / Length / Slices / slices in go. it is the repetition of a process within a go program. Golang has the ability to declare and create own data types by combining one or more types, including both built-in and user-defined types. 6 (9,273 ratings) Course Ratings are calculated from individual students' ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. A core data structure for this is a map of string. But slices can be dynamic. Golang: How to build/create RESTful APIs with Golang (Go programming language) in a couple of hours. A practical step-by-step Golang tutorial with code samples. Please add the following code above the main function. Flexible length. They're different from what you're used to in dynamic languages, but very powerful. Structs and Interfaces. Take a simple slice of structs: type Post struct { Name string ID int } var list [] Post. package main. An easier approach would be changing the Tags field of the Task struct to string and do this conversion somewhere in the application code before persisting the task. A slice is a segment of dynamic arrays that can grow and shrink as you see fit. The doc you referenced to states that A nil slice has a length and capacity of 0 but not that every slice of length and capacity of zero is a nil slice. If you could delete an element by swapping it with the last one in the slice and shrinking the slice by 1, or by zeroing a struct field or pointer. The service receives a Go program, vets , compiles, links, and runs the program inside a sandbox, then returns the output. Our example shows us creating a slice and then printing out it's length, then adding an extra item and printing the length again. We are returning JSON data with only the Person struct, not the entire N1qlPerson struct. With maps, it returns the key of the next key-value pair. With time I've added other utilities for structs. It's the deletes that concern me most, because each will require shifting, on average, half the array. In fact, it is so popular that you may even go ahead and call it the de-facto data interchange format on the internet. Ten Reasons Why I Don't Like Golang. Theory and Practice About Archives Categories Tags Authors 中文 ไทย. Go’s structs are typed collections of fields. The type system is the most important feature of. As it stands now, attempts to perform ancestor queries within a namespace fail with a BadRequest: The query namespace is "null"; but ancestor namespace is "foo". Golang has the ability to declare and create own data types by combining one or more types, including both built-in and user-defined types. There's a few things to consider while creating JSON in Go. In general, carefully selected data structure can bring higher operation or storage efficiency. Using Maps. Matthew Setter covers Arrays, Slices and Basic OOP in Go. 12/7/2018 · I have a slice of structs. go, here https. Go Slices: usage and internals. Day 17 - Using reflection to write into an interface slice How to use reflection to write into a slice of unknown items inside an unknown struct: While working on Gorp with Indexes i had to solve the problem of how to write into a slice inside a struct passed as an interface{}. It defines a collection of "fields", each field is a name and a value of a specific type. Other values - numbers, bools, strings, and channels - are deeply equal if they are equal using Go's == operator. Devolopers new to Golang typically have a good understanding of Arrays and Slices, but there always seems to be a small piece missing which leads to much confusion. Fortunately, Go tries to make this process as easy for us as possible,. The Go Playground is a web service that runs on golang. Slices have a capacity and length property. Slice is an essential component of Go programming language. This selects a half-open range which includes the first element, but excludes the last one. This golang tutorial convert STRUCT data into JSON and from JSON to string using marshaling and unmarshalling. // Creating a slice using a slice literal var s = []int{3, 5, 7, 9, 11, 13, 17} The expression on the right-hand side of the above statement is a slice literal. type person struct { name string age int} Look how easy it is to define a struct!. A struct is a user-defined type that contains the collection of named fields/properties. Working with a language like Go means you have to make the variable structure of JSON fit into structured variables. Like arrays, slices are index-able and have a length. Slices can also be defined with capacity and length. In practice, slices are much more common than arrays. We can define new types of containers of other properties or fields in Go just like in other programming languages. If the program contains tests or examples and no main function, the service runs the tests. I am wondering if this is idiomatic and okay usage of the go languages. Eg: arr[0:5] will give a slice of first 5 elements of an array. Slices of structs are valid, as are structs that contain slices. A struct. Views: Quick tip. However, the effect is essentially the same as thinking of it as a slice. We are returning JSON data with only the Person struct, not the entire N1qlPerson struct. What is a structure? A structure is a user defined type which represents a collection of fields. I am wondering if this is idiomatic and okay usage of the go languages. You might remember my heap corruption during garbage collection post. Go supports several serialization formats in the encoding package of its standard library. go, here https. Day 17 - Using reflection to write into an interface slice How to use reflection to write into a slice of unknown items inside an unknown struct: While working on Gorp with Indexes i had to solve the problem of how to write into a slice inside a struct passed as an interface{}. はじめに Pointer Structs Arrays Slice Range Map function values はじめに どうも、年末にアドカレを1日分書き忘れていたので急いで書き始めたけんつです。 今回も例によって全くPHPは関係無いですが、A Tour of Go の続きをやっていこうかなと思います。. We call this kind of type a struct. go Syntax Imports. Although it would be possible for us to write programs only using Go's built-in data types, at some point it would become quite tedious. Golang Tutorial: 10 Most Common Examples Golang (or just "Go") is gaining popularity with big companies, startups, and developers - and it's easy to see why. How to Use Structs in Golang. Here's the syntax for specifying for loop in Golang:. It is sometimes called a structure or aggregate data type, although the latter term may also refer to arrays, lists, etc. They're useful for grouping data together to form records. 90%+ of the time the you work with lists of values in Go, you will be working with slices, not arrays. the slices use instead of arrays because they are flexible, you can change their size, you can increase them in size. With Go, you can find the length of an array (or more accurately a slice) by using the internal len() function. Slice Length and Capacity in Golang 36. Slices are made up of three things, a pointer, a length, and a capacity. Go Structs Tutorial With Example | Structs In Golang Explained is today's topic. slices Why can't I append to a slice that's the property of a struct in golang? golang string slice (4) I'm trying to append a value to a golang slice, the code works if it's called in the first method, but if this method calls another method, the code seems to fail. It's basically a high level package based on primitives from the reflect package. Golang Cheat Sheet. A common use of Search is to find the index i for a value x in a sorted, indexable data structure such as an array or slice. Golang for loop With Range. Slices are somewhat similar to arrays but with more flexibility. [code]type myStruct struct { a string b int } func getSliceOfStructs() []myStruct { myStructs := []myStruct{ {a: "S1", b: 1}, {a: "S2", b: 2}, {a: "S3", b. 0 was released at 2012. A slice is a data structure describing a contiguous section of an array stored separately from the slice variable itself. So that to avoid expensive copying of the whole struct in memory. CODE EXAMPLE How to sort any type of data in Go using the sort package. A slice is a segment of dynamic arrays that can grow and shrink as you see fit. Let's try and visualize this with an example. In this post, we'll take a look at the type system of Go, with a primary focus on user-defined types. encoding/gob and encoding/json do, among others. org/moretypes/7. A struct is a user-defined type that contains the collection of named fields/properties. Range either returns one value or two. A struct is defined with the type and struct keywords. It returns a pointer to the newly created struct. Golang: Passing a slice of variables to a function as multiple arguments. The Go Playground is a web service that runs on golang. Structs contains various utilities to work with Go (Golang) structs. This disqualifies recursively defined struct types: any struct T that (directly or indirectly) contains a []T. Append Item to Slice in Golang 34. Maps and slices are reference types in Go and should be passed by values. Feel free to add new functions or improve the existing code. It is sometimes called a structure or aggregate data type, although the latter term may also refer to arrays, lists, etc. Go's slice type provides a convenient and efficient means of working with sequences of typed data. Although it would be possible for us to write programs only using Go's built-in data types, at some point it would become quite tedious. Don’t create structs that have a duality of nature. Golang has gained tremendous grounds in Software development in few years of its launch. Array – Well, almost every programmer knows what is array. To define a structure, you must use type and struct statements. In terms of syntax, structure, and philosophy, here's the shortest way to compare Python and Go: same… There are some similarities between Go and Python. They're different from what you're used to in dynamic languages, but very powerful. // Creating a slice using a slice literal var s = []int{3, 5, 7, 9, 11, 13, 17} The expression on the right-hand side of the above statement is a slice literal. Flexible length. A slice is a flexible and extensible data structure to implement and manage collections of data. In practice, slices are much more common than arrays. It contains a majority of the common features avialble to users/content editors, but may not have complete coverage of the featureset. How about a slice? We could make a slice with SliceExample []float32. To give an idea, Data + PrevHash would produce a certain amount of data, which in turn we could use to make a sha256 hash. It is used to group related data to form a single unit. the slices use instead of arrays because they are flexible, you can change their size, you can increase them in size. The only way to avoid this would be to allocate a fixed-size array (like [10000]int ). A struct (short for "structure") is a collection of data fields with declared data types. Size of struct is counted accordingly with padding and alignment rules. In this case, the argument f, typically a closure, captures the value to be searched for, and how the data structure is indexed and ordered. The number of elements in a slice can grow dynamically. The built-in append function appends any number of elements to the end of a slice. data is the variable to store training data. Append Item to Slice in Golang 34. can be resized. A Slice is a light weight data structure that gives access to sequence of elements of an array, also known as slice’s underlying array. Structures are used to represent a record. the ColoredThing interface will be implemented by two different structs, both of which have the same underlying properties. Cast an interface/struct in golang Oct 25, 2017 15:45 · 222 words · 2 minutes read golang programming type casting interface in golang can be useful when you build a modular app using golang. Go supports several serialization formats in the encoding package of its standard library. Underlying the slice is an array and a pointer to it, exactly how the Go compiler stores the slice is a little complex, we will cover it in the "Intermediate" section of the tutorial. Sort Slice of Numbers in Golang 40. Then we pass it to the request with the proper content type. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. A slice is a data structure describing a contiguous section of an array stored separately from the slice variable itself. So that to avoid expensive copying of the whole struct in memory. But, keep in mind that slice uses. Structures are used to represent a record. Structure¶ Navigate to our code folder. Go allow you to define variables that can hold several data items of the same kind. Range either returns one value or two. Welcome to tutorial no. Friday, Sep 11th, 2015. To get the size of the underlying structure, you want to use cap. by Ramesh Natarajan. Devolopers new to Golang typically have a good understanding of Arrays and Slices, but there always seems to be a small piece missing which leads to much confusion. org's servers. / golangci-lint: lint check, golint: errcheck: errcheck checks that you checked errors, errcheck. / delve: Delve is a debugger for the Go programming language. When writing a go program, for most common use-cases, you’ll be using slice instead of array. In Elixir, you can return the number of characters in a string with the String. For instance a employee has a firstName, lastName and age. They are useful when you want to group your data to form the records. Each data field in a struct is declared with a known type, which could be a built-in type or another user-defined type. A slice gives much more flexibility. If you could delete an element by swapping it with the last one in the slice and shrinking the slice by 1, or by zeroing a struct field or pointer. co/TUtqSagEnV - Simple Golang tutorials with lots of code samples. Example: var sl []int; var sl []string [see Golang: Basic Datatypes]. This disqualifies recursively defined struct types: any struct T that (directly or indirectly) contains a []T. Struct in Golang // Go's _structs_ are typed collections of fields. You serialize Golang values using the Marshal() function into a slice of bytes. This query is a parameterized query to prevent SQL injection. When you use slices of structs, keep in mind that every time you retrieve an element or put an element, a new copy of the struct variable is created. You might remember my heap corruption during garbage collection post. This is what some call "Duck Typing" meaning, "If it walks like a duck and sounds like a duck then it must be a duck. Save variables of any type (struct, map, array, slice, etc. Notice that only for slices of structs the slice index is required. Let's define the website struct first. Golang Range | Range In Golang - The range keyword is used in for loop to iterate over items of an array, slice, channel or map. It's not uncommon for public JSON APIs to reply with top level arrays, instead of a full JSON object. Friday, Sep 11th, 2015. This article will look at what slices are and how they are used. Golang Cheat Sheet. There are 3 components of slice:a) Pointer: Points to the start position of slice in the underlying array;b) length (type is int): the number of the valid elements of the slice;b) capacity (type is inPixelstech, this page is to provide vistors information of the most updated technology information around the world. length/1 function: Discussion In the case of a string like, “Myzigyasa”, there isn’t much to discuss. proto to share with others. はじめに Pointer Structs Arrays Slice Range Map function values はじめに どうも、年末にアドカレを1日分書き忘れていたので急いで書き始めたけんつです。 今回も例によって全くPHPは関係無いですが、A Tour of Go の続きをやっていこうかなと思います。. It returns a pointer to the newly created struct. If the program contains tests or examples and no main function, the service runs the tests. boolean, slice, struct, slice of struct. Go Cheat Sheet Credits Most example code taken from A Tour of Go, which is an excellent introduction to Go. Golang Slice provides many inbuilt functions, which we will go through them in this tutorial. How to Parse JSON in Golang (With Examples) October 18, 2017 (Updated on June 26, 2019) In this post, we will learn how to work with JSON in Go, in the simplest way possible. /* Slice as a structure */ type slice struct { Length int Capacity int ZeroElement *byte} As we pass slice (actually structure) to the function, the pointer will still refer to the same underlying array, so any changes to the array (through the slice) done in the function are available even after the function scope. Looks like removing the anonymous struct is the way to Go as everyone suggested. Take a simple slice of structs: type Post struct { Name string ID int } var list [] Post. Let's see how we could implement it. Developers can write code and build applications as quickly and easily as possible with these helpful tools. As an exercise for myself, I started writing a Tic-Tac-Toe solver in Golang to get the hang of the language. A Slice is a light weight data structure that gives access to sequence of elements of an array, also known as slice’s underlying array. Garbage collection is a convenient feature of Go - automatic memory management makes code cleaner and memory leaks less likely. This Golang tutorial help to understand marshalling and un-marshalling of data using Golang. In general, carefully selected data structure can bring higher operation or storage efficiency. A slice, on the other hand, is a dynamically-sized, flexible view. org/moretypes/7. Slices of structs are valid, as are structs that contain slices. One of these is the popular JSON format. Posts about golang written by xebiaww. Slices: Numbered list of a single type. In Golang, a slice is a reference to a contiguous segment of an array. Say, for instance, we have an array of the days of the week, we could use slices to extract only those days that are week days. The document id from the meta information is being compared against the document id parameter that was passed in with the route request. The slice is a variable-length sequence which stores elements of a similar type, you are not allowed to store different type of elements in the same slice. Go's slice type provides a convenient and efficient means of working with sequences of typed data. Now, each of our Node structs will have a tag, children which is a slice of pointers to the children of that Node, id which is the ID of that DOM node and class which is the classes that can be applied to this DOM node. type House struct { } func (h House) GetHouseName() string { } //method defined outside of struct, but works on House Now let's learn how to create structs and their specialities in Go that allows us to get all the goodness of object oriented programming without actually needing it. Slice can represent either entire array or portion of array as needed. Go Cheat Sheet Credits Most example code taken from A Tour of Go, which is an excellent introduction to Go. A Slice is like a dynamically-sized array. Other values - numbers, bools, strings, and channels - are deeply equal if they are equal using Go's == operator. Structs and Interfaces. skybrian on Dec 25, 2016 I agree that the way Rust does type checking for ownership is pretty cool, but transferring ownership without having static analysis verify it seems pretty normal. golang - some constructs part 1 Jon Langemak August 7, 2015 August 7, 2015 No Comments on golang - some constructs part 1 Since starting to play with golang I've run into a couple of interesting items I thought worth writing about. Initially, I hesitated in doing it in Go since it didn't look easy. A slice of structures (golang) This time a slice (a Go open ended array) of structures is used as a record for some data processing. In the previous post “A Closer Look at Golang From an Architect’s Perspective,” we offered a high level look at the Go programming language. Now, back to our getElementById lookup function. I’ve seen quite a bit of community interest in learning Go but not a lot of material around it. In Go we use the keyword range within a for loop construct to iterate over a slice. Tic-Tac-Go! A Tic-Tac-Toe solver in Golang. One of these is the popular JSON format. The Go Playground is a web service that runs on golang. In this post, we’ll take a look at the type system of Go, with a primary focus on user-defined types. I am wondering if this is idiomatic and okay usage of the go languages. label is the variable to store training data's labels. Println outputs the length(3), capacity(5) and the starting element address(0xc820010240) of the slice, let's check the memory layout of s1:. 6 (9,273 ratings) Course Ratings are calculated from individual students' ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. Cast an interface/struct in golang Oct 25, 2017 15:45 · 222 words · 2 minutes read golang programming type casting interface in golang can be useful when you build a modular app using golang. An easier approach would be changing the Tags field of the Task struct to string and do this conversion somewhere in the application code before persisting the task. Normally, append will always result a slice with capacity greater than 1st arg slice_x, therefore a new slice is created and slice_x is not modified. Pretty print variable (struct, map, array, slice) in Go. It can be used in places where it makes sense to group the data into a single unit rather than maintaining each of them as separate types. Here's a list of the top Golang tools for your reference. You then call the getRepo() function to obtain a repository corresponding to the key 1 and store the returned value in the repositories slice using the append() function. A slice is a flexible and extensible data structure to implement and manage collections of data. Struct in Golang // Go's _structs_ are typed collections of fields. Data structure refers to the collection of data elements that have one or more specific relationships with each other. In Go we use the keyword range within a for loop construct to iterate over a slice. You might remember my heap corruption during garbage collection post. For those who miss the ; at the end of a line of code, you can use them, but the lexer of the compiler will put them in for you. Fortunately, it's easy to accomplish this task using the Bulk() API method to index Elasticsearch documents with the help of the Olivere Golang driver. Pointer Len int Cap int } slice 的秘诀在于取出指向数组头部的指针,然后具体的. Once you defined a struct type (with a given name), you can create struct of that name. A Slice is a light weight data structure that gives access to sequence of elements of an array, also known as slice’s underlying array. Alright, back to our example, we've got a struct that at least gets us through to the sitemap XML tag, and then we know that we're going to build a slice called Locations, which is made up for data of the type Location. Slices are where the action is, but to use them well one must understand exactly what they are and what they do. The slice is a variable-length sequence which stores elements of a similar type, you are not allowed to store different type of elements in the same slice. Structs and Interfaces. Two structs with same fields but different order may have different sizes. HGPA Golang. Slice can represent either entire array or portion of array as needed. Golang Tutorial: 10 Most Common Examples Golang (or just "Go") is gaining popularity with big companies, startups, and developers - and it's easy to see why. The map struct is harder to find, but it exists: hmap. If you could delete an element by swapping it with the last one in the slice and shrinking the slice by 1, or by zeroing a struct field or pointer. GOLANG,JSON,EMPTY SLICE,NIL SLICE. Golang GC • Generational – memory is divided into regions based on certain tenuring policies: no need to scan everything every time. A practical step-by-step Golang tutorial with code samples. The service receives a Go program, vets , compiles, links, and runs the program inside a sandbox, then returns the output. A slice describes a piece of an array. Devolopers new to Golang typically have a good understanding of Arrays and Slices, but there always seems to be a small piece missing which leads to much confusion. GoLang Slice of Structs. The Go Playground is a web service that runs on golang. To define a new struct type, you list the names and types of each field. A slice is a reference to a section of an array. The slice is a variable-length sequence which stores elements of a similar type, you are not allowed to store different type of elements in the same slice. A Slice is like a dynamically-sized array. Golang is an attempt to combine the ease of programming of an interpreted, dynamically typed language with the efficiency and safety of a statically typed, compiled language. type KNN struct { k int data [][] float64 labels [] string} kNN structure has k, data and label. Go's slice type provides a convenient and efficient means of working with sequences of typed data. It changes the underlying structure of the array it references. [citation needed] Types. Cast an interface/struct in golang Oct 25, 2017 15:45 · 222 words · 2 minutes read golang programming type casting interface in golang can be useful when you build a modular app using golang. A slice in Golang is an dynamically sized array—similar to a list in Python. You missed my favorite use for the empty struct: singletons! Where an OOP programmer would use some variant of the Singleton design pattern, to ensure that only one instance of his class is created, in Go you can use an empty struct, and store all your data in global variables. Loading an array/slice of objects from a JSON file in Golang As usual, with a new project arriving my first question is "what can we learn on this one?" So, having found that Go (aka Golang) is a decendant of Modula-2 and has some pretty nifty features, I decided that Golang was the way to Go (if you will pardon the expression). The definition of a method attached to or associated with a struct or any other type for that matter, is quite similar to a normal func definition, the only difference being that you need to additionally specify the type. If you could delete an element by swapping it with the last one in the slice and shrinking the slice by 1, or by zeroing a struct field or pointer. You might remember my heap corruption during garbage collection post. The map struct is harder to find, but it exists: hmap. 4 struct struct. org's servers. the slices use instead of arrays because they are flexible, you can change their size, you can increase them in size. Tutorials [77] Results. proto to share with others. For instance a employee has a firstName, lastName and age. Andrew Gerrand 5 January 2011 Introduction. where slicename is the name using which we can refer to the slice. Go slices are simpler to work with and faster than traditional arrays,. However, if slice_x is a slice of slice slice_w, and append result is less than capacity of slice_w, then slice_w is modified. Although it would be possible for us to write programs only using Go's built-in data types, at some point it would become quite tedious. Easy enough, but storing your query result in a map is a bit trickier. In Go language slice is more powerful, flexible, convenient than an array, and is a lightweight data structure. This is what some call "Duck Typing" meaning, "If it walks like a duck and sounds like a duck then it must be a duck. At first, it's easy to see arrays and slices as the same thing: a data structure to represent collections.