Number of Call Levels

Maximum depth of nesting of control flow structures

Description

This metric specifies the maximum nesting depth of control flow statements such as if, switch, for, or while in a function. A function without control-flow statements has a call level 1.

The recommended upper limit for this metric is 4. For better readability of your code, try to enforce an upper limit for this metric.

To enforce limits on metrics, see Compute Code Complexity Metrics.

Examples

Function with Nested if Statements

int foo(int x,int y)
{
    int flag = 0;
    if (x <= 0)
        /* Call level 1*/
        flag = 1;
    else
    {
        if (x <= y )
            /* Call level 2*/
            flag = 1;
        else
            flag = -1;
    }
    return flag;
}

In this example, the number of call levels of foo is 2.

Function with Nesting of Different Control-Flow Statements

int foo(int x,int y, int bound)
{
    int count = 0;
    if (x <= y)
        /* Call level 1*/
        count = 1;
    else
        while(x>y) {
            /* Call level 2*/
            x--;
            if(count< bound) {
                /* Call level 3*/
                count++;
            }
        }
    return count;
}

In this example, the number of call levels of foo is 3.

Metric Information

Group: Function

Acronym: LEVEL

HIS Metric: Yes