Go Concepts - The Type System: Difference between revisions

From NovaOrdis Knowledge Base
Jump to navigation Jump to search
Line 39: Line 39:


<font color=red>Can only structs be interfaces, or there are other things that can be interfaces?</font>
<font color=red>Can only structs be interfaces, or there are other things that can be interfaces?</font>
=Built-in Types=
==Arrays==
==Slice==
A ''slice'' is a reference type that implements a ''dynamic array''.
Slice built-in functions <tt>[[go Built-In Function append|append()]]</tt>, <tt>[[go Built-In Function copy|copy()]]</tt>.
<font color=red>'''TODO''' Deep difference between slice and array (memory model, etc.)</font>
==Maps==


=Reference Types=
=Reference Types=

Revision as of 07:24, 22 March 2016

Internal

Overview

Go is statically typed. Go designers tried to alleviate some of the "heaviness" associated with statically typed languages and made it "feel" like a dynamic language. For example Go uses local type inference, which eliminates the need to specify the type unnecessarily in program, the compiler figures it out.

Go is strongly typed meaning that yes cannot be unsafely coerced into other types they're not, or at least without programmer giving explicit permission. In JavaScript, for example, implicit conversion is done based on complicated rules that are not always easy to remember.

For more details on typing, see static typing vs. dynamic typing and strong typing vs. loose typing.

Type Definition

Type Definition

Value and Reference Types

Zero Value

Zero value for a specific type: 0 for ints, 0.0 for floats, "" for string, false for Booleans and nil for pointers. For reference types, their underlying data structures are initialized to their zero values.

Number

String

String Operators and Functions

User-Defined Types

struct

Are all users can define (in terms of types) structs, or there are other user-defined types?

interface

Can only structs be interfaces, or there are other things that can be interfaces?

Reference Types

Conversion Between Types

Primitive vs. Non-Primitive Nature

Duck Typing

For more details on duck typing go here.


Structs

Fields

A field is always exported by the package it is enclosed in.

Interfaces

Interfaces are not types.