Bash Arrays: Difference between revisions

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  echo ${a[0]}
  echo ${a[0]}
If the specific element was not initialized, or the array variable does not exist, the reference attempt will return the blank string.


==Use Cases==
==Use Cases==


=Associative Arrays=
=Associative Arrays=

Revision as of 21:26, 23 February 2018

Internal

Indexed Arrays

External

Overview

bash indexed arrays are 0-based and unidimensional. No explicit declaration is necessary if at least one element is initialized as described below:

Declaration

Initialization

Individual elements are initialized by using ${var-name[index]}=value notation:

a[0]="something"

Reference

Element arrays can be referenced with ${var-name[index]} notation:

echo ${a[0]}

If the specific element was not initialized, or the array variable does not exist, the reference attempt will return the blank string.

Use Cases

Associative Arrays