Code inspection: Local variable has too wide declaration scope

JetBrains Rider suggests moving the declaration of a local variable closer to its usage. If a variable is not used outside a block of instructions, it is a good practice to declare it within that block.

In the example, JetBrains Rider suggests moving the declaration of tmpvar inside the for loop, where tmpvar is used.

            
private static char[] MyMethod(char[] x)
{
    char tmpvar;
    for (int i = 0; i < x?.Length / 2; i++)
    {
        tmpvar = x[i];
        x[i] = x[x.Length - 1 - i];
        x[x.Length - 1 - i] = tmpvar;
    }
    return x;
}


        

            
private static char[] MyMethod(char[] x)
{
    for (int i = 0; i < x?.Length / 2; i++)
    {
        var tmpvar = x[i];
        x[i] = x[x.Length - 1 - i];
        x[x.Length - 1 - i] = tmpvar;
    }
    return x;
}

        

If possible, JetBrains Rider will automatically join the declaration and assignment, and according to the default preferences will change the explicit variable type to var when it applies this quick-fix.

Last modified: 08 April 2024