Types
int, uint, float32, float64, bool, string
Control Structures
if-else
for
switch
Arrays, Slices and Maps
Arrays - indexable, single type, fixed length
Slices - indexable, single type but length is allowed to change; use make function to craete a slice; append; copy;
Maps - unordered, key-value pairs; initialize before use; make; delete;
Functions
named return type
multiple returned values
variadic parameters
closure - create functions inside function
recursion
defer - scheduled a function call to be run after the function completes; often used for resources releasing;
panic - indicates a programmer error
recover - handle a runtime panic
Pointers
pointers reference a location in memory where a value is stored rather than the value itself
pointer is represented using the * character followed by the type of the stored value
* is also used to "dereference" pointer variables
use & operator to find the address of a variable
new - take a type as an argument, allocates enough memory to fit a value of that type, returns a pointer to it
Structs and Interfaces
struct - a type which contains named fileds; create methods for structs
interface - not like struct contains fields, in interface we define "method sets"
Concurrency
goroutine - use keyword go followed by a function invocation to create a goroutine; the first goroutine is implicit and is the main function itself;
channel - it provides a way for two goroutines to communicate with one another and synchronize their executions
channel directions - specify a direction on a channel type thus restricting it either sending or receiving
select - works like switch but for channels; often used to implement a timeout;
time.after
buffered channel - specifiy capacity
packages
testing
1 package math
2
3 import "testing"
4
5 func TestAverage(t *testing.T) {
6
7 ...
8
9 }
Core Packages
strings - a large number of functions working with strings
input/output - io package consists of a few functions, but mostly interfaces used in other packages; two main interfaces are Reader and Writer.
files & folders - os package
errors - errors package; error.New("...")
containers & sort
- container/list - implement a doubly-linked list
- sort - contains functions for sorting arbitrary data; sort.Interface requires 3 methods: Len, Less, Swap, any type defined these 3 methods can be sorted.
hashes & cryptography - non-cryptographic hash functions in hash/adler32, crc32, crc64, fnv; cryptographic hash functions in crypto/sha1, crypto/md5, etc.
servers - net, net/http, net/rpc, etc
parsing command line args - flag package
synchronization primitives - Go provides more traditional multithreading routines in sync and sync/atomic packages