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The Go Programming Language
book

The Go Programming Language

by Alan A. A. Donovan, Brian W. Kernighan
October 2015
Beginner to intermediate content levelBeginner to intermediate
400 pages
14h 44m
English
Addison-Wesley Professional
Content preview from The Go Programming Language

3.6 Constants

Constants are expressions whose value is known to the compiler and whose evaluation is guaranteed to occur at compile time, not at run time. The underlying type of every constant is a basic type: boolean, string, or number.

A const declaration defines named values that look syntactically like variables but whose value is constant, which prevents accidental (or nefarious) changes during program execution. For instance, a constant is more appropriate than a variable for a mathematical constant like pi, since its value won’t change:

const pi = 3.14159 // approximately; math.Pi is a better approximation

As with variables, a sequence of constants can appear in one declaration; this would be appropriate ...

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Publisher Resources

ISBN: 9780134190570Purchase book