Go Basics

Links: 103 Golang Index

Features of Go¶

Go is a statically typed programming language which means it does type checking at compile time. Some other statically typed languages are C, C++, Java.
- In case of Go you can explicitly declare the types or it can be inferred during compile time.
A dynamically typed language like Python or PHP does type checking at runtime.
Go is also a strongly typed language which means you cannot assign a type to a variable with another type.
- You would need type casting to do this var a,b = 10,4.5; a = int(b)
- You cannot multiply int with float.

Convention is to use camelCase for writing multi word names instead of snake_case. This is applicable to variables, functions and constants. maxValue := 343
Acronyms should be in all caps : writeToDB := true
By convention packages are given small case single word names

Don't use variables with capital letters in the program as they will be exported by Go to be used in other packages.

x++, x-- works
== equality check
a < 5 && b > 10 - second operation is evaluated only if first one is true. short circuit.
A float number overflows to infinity

Println :
- a := "test"; fmt.Println("hello", a) - hello test
- Spaces are always added between operands and a newline is appended
Printf :
- The first argument is the template string that contains the text you want to format plus some annotation verbs (Eg: %d) that tell the function how to format the trailing arguments.
- Number of verbs should be equal to the number of passed values.
  - %d - integer. d comes from decimal
  - %f - float. %.3f - only show 3 decimal points
  - %s - string
  - %q - double-quoted strings. Eg: a := "hello"; fmt.Printf("How %q",a) - How "hello"
  - %v - can be replaced by any value
  - %#v- a Go-syntax representation of the value
  - %+v - to print the struct's values and fields
  - %T - print the type of the variable
  - %t - for boolean values
  - %p - for pointer address. Address in base 16, with leading 0x
Sprintf - returns a string. Uses the same verbs as Printf()
- s := fmt.Sprintf("hello %d", a)

Last updated: 2022-05-29