How to Fix 'Assignment to Entry in Nil Map' Error When Creating a Slice of Maps in Go?

Runtime Error: "Assignment to Entry in Nil Map" Resolved

When attempting to create a slice of Maps, you may encounter the runtime error "assignment to entry in nil map." This error indicates that you are trying to access a nil Map value, which is not permitted.

Problem Statement

You are experiencing this error while building an array of Maps, each containing two keys: "Id" and "Investor." The attempted code is as follows:

<code class="go">for _, row := range rows {
    invs := make([]map[string]string, length)

    for i := 0; i <p><strong>Resolution</strong></p>
<p>To resolve this error, you should create a slice of Maps directly within the loop instead of creating nil Maps and assigning values to them. This can be achieved using composite literals:</p>
<pre class="brush:php;toolbar:false"><code class="go">for _, row := range rows {
    invs := make([]map[string]string, length)

    for i := 0; i <p><strong>Alternative Approach</strong></p>
<p>Alternatively, you can use a struct to represent an investor:</p>
<pre class="brush:php;toolbar:false"><code class="go">type Investor struct {
    Id       int
    Investor string
}

for _, row := range rows {
    invs := make([]Investor, length)

    for i := 0; i <p>Using a struct provides a cleaner and more structured representation of your data.</p></code>

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