Why Does My Recursive Function Return `None` Instead of `True` When It Finds the Character?

Why Does Recursive Code Return None?

In the provided code snippet, a recursive function, isIn, is defined to determine whether a given character exists within a string. However, it consistently returns None instead of the expected True value when the character is found within the string.

The code performs a binary search on the string, repeatedly dividing it in half. When the character is found at the midpoint, it prints a message indicating its location, but it fails to return True.

To rectify this issue, a return statement should be added to the last line of the function, as seen below:

<code class="python">return isIn(char, aStr)</code>

Without this return statement, the function simply returns None when it terminates without encountering a return statement. By adding this return, the function can properly return True when the character is located within the string.

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