My learning journey in Go lang
go build creates an executable file for later use in Go lang
go run compiled the go file and run it to machine
Package main is special. It defines a standalone executable program, not a library. Within package main the function main is
also special—it’s where execution of the program begins
“The import declarations must follow the package declaration.”
This version of program uses a short variable declaration to declare and initialize s
and sep
, but we could equally well have declared the variables separately. There are several ways to declare a string variable; these are all equivalent.
s := ""
var s string
var s = ""
var s string = ""
- The first form a short variable declaration, is the most compact, but it may be used only within a function, not for package-level variables.
- The second variable relies on default initialization to zero value for string, which is
""
.
The built-in function make
creates a new empty map
Printf has over a dozen such conversions, which Go programmers call verbs. This table '
%d decimal integer %x, %o, %b integer in hexadecimal, octal, binary
%f, %g, %e floating-point number: 3.141593 3.141592653589793 3.141593e+00
%t boolean: true or false
%c rune (Unicode code point)
%s string
%q quoted string "abc" or rune 'c'
%v any value in a natural format
%T type of any value
%% literal percent sign (no operand)”
Excerpt From The Go Programming Language (Addison-Wesley Professional Computing Series) Brian W. Kernighan This material may be protected by copyright.