GOLANG
The anatomy of maps in Go
A map is a composite data type that can hold data represented by key:value
pairs.
☛ What is a map
?
A map is like an array
except, instead of an integer index
, you can have string
or any other data types as a key
. An illustration of a map looks like
{
stringKey: intValue,
stringKey: intValue
...
}
The syntax to define a map is
var myMap map[keyType]valueType
Where keyType
is the data type of map keys while valueType
is the data type of map values. A map
is a composite data type because it is composed of primitive data types (see variables lesson for primitive data types).
Let’s declare a simple map.
In the above program, we have declared a map m
which is empty, because zero-value
of a map is nil
. But the thing about nil
map is, we can’t add values to it because like slices, map
cannot hold any data, rather they reference the internal data structure that holds the data.