Go Keyword range: Difference between revisions
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=Internal= | =Internal= | ||
* [[Go_Language#range_keyword|Go Language]] | |||
=Overview= | |||
<code>range</code> can be used to iterated through [[Go_Channels#Iterative_Read_from_a_Channel|channels]]. | |||
=Iterating through Arrays= | |||
{{Internal|Go_Arrays#Iterating_though_Arrays|Iterating though Arrays}} | |||
=Iterating through Slices= | |||
{{Internal|Go_Slices#Iterating_through_Slices|Iterating through Slices}} | |||
=Iterating over Map Keys and Values= | |||
{{Internal|Go_Maps#Iterating_over_a_Map|Iterating over Map Keys and Values}} | |||
=TO PROCESS= | |||
<font color=darkkhaki> | |||
==Internal== | |||
* <tt>[[Go for#for_Controlled_by_a_.22range.22_Clause|for]]</tt> | * <tt>[[Go for#for_Controlled_by_a_.22range.22_Clause|for]]</tt> | ||
* [[Go Channels|Channels]] | |||
==Overview== | |||
<tt>range</tt> keyword is used to iterate over strings, [[Go_Arrays#Iterating_over_Arrays|arrays]], [[Go_Slices#Iterating_over_Slices|slices]], [[Go_Maps#Iterating_over_Maps|maps]], channels and [[Go_Concepts_-_Functions#Varidic_Functions|variadic function arguments]]. It returns two values. On the first position is the index/key, and on the second position is the ''copy'' of the value in that element. For slices and arrays, <tt>range</tt> always starts to iterate from index 0. If you need more control over the start index, use a <tt>[[Go_for#Iterating_over_a_slice_from_a_non-zero_index|for]]</tt> loop. | |||
< | <blockquote style="background-color: Gold; border: solid thin Goldenrod;"> | ||
:Note 1: that only a first identifier is declared, that is the ''index'' and not the value, as the intuition would suggest. See examples below.<br> | |||
</blockquote> | |||
<blockquote style="background-color: Gold; border: solid thin Goldenrod;"> | |||
:Note 2: <tt>range</tt> returns a ''copy'' of the value, in the same way it would pass an argument to a function. It does NOT return a reference to the element in the structure it iterates over.<br> | |||
</blockquote> | |||
==Iterating over Key/Values in a Map== | |||
<pre> | <pre> | ||
m := map[string]string { | |||
for | "k1": "v1", | ||
"k2": "v2", | |||
"k3": "v3", | |||
} | |||
for key, value := range m { | |||
// | |||
} | } | ||
</pre> | </pre> |
Latest revision as of 00:00, 27 August 2024
Internal
Overview
range
can be used to iterated through channels.
Iterating through Arrays
Iterating through Slices
Iterating over Map Keys and Values
TO PROCESS
Internal
Overview
range keyword is used to iterate over strings, arrays, slices, maps, channels and variadic function arguments. It returns two values. On the first position is the index/key, and on the second position is the copy of the value in that element. For slices and arrays, range always starts to iterate from index 0. If you need more control over the start index, use a for loop.
- Note 1: that only a first identifier is declared, that is the index and not the value, as the intuition would suggest. See examples below.
- Note 2: range returns a copy of the value, in the same way it would pass an argument to a function. It does NOT return a reference to the element in the structure it iterates over.
Iterating over Key/Values in a Map
m := map[string]string { "k1": "v1", "k2": "v2", "k3": "v3", } for key, value := range m { // }