<div dir="ltr"><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:rgb(51,0,51)">Thank you Alan. But a question here, how would it understand that the given input is valid?</div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:rgb(51,0,51)"><br></div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:rgb(51,0,51)"><br></div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:rgb(51,0,51)"><br></div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:rgb(51,0,51)"><span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px">The while loop makes it keep on asking until a valid input is</span><br style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px"><span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px">received. Without the while loop it would only ask once and</span><br style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px"><span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px">either return None or a digit.</span><br style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px"></div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:rgb(51,0,51)"><span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:13px"><br></span></div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:rgb(51,0,51)"><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Nov 26, 2014 at 3:46 PM, Alan Gauld <span dir="ltr"><<a href="mailto:alan.gauld@btinternet.com" target="_blank">alan.gauld@btinternet.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">On 26/11/14 09:57, Sunil Tech wrote:<br>
</span><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">
Hi Danny,<br>
<br>
Curious to the use the need of using while True in the given example of<br>
ask_for_a_digit().<br>
<br>
<br>
On Mon, Nov 17, 2014 at 9:57 AM, Danny Yoo <<a href="mailto:dyoo@hashcollision.org" target="_blank">dyoo@hashcollision.org</a><br></span><span class="">
<mailto:<a href="mailto:dyoo@hashcollision.org" target="_blank">dyoo@hashcollision.org</a><u></u>>> wrote:<br>
<br>
    > def ask_for_a_digit():<br>
    >     while True:<br>
    >         digit = raw_input("Give me a digit between 0 and 9.")<br>
    >         if digit not in "0123456789":<br>
    >             print "You didn't give me a digit.  Try again."<br>
    >         else:<br>
    >             return int(digit)<br>
</span></blockquote>
<br>
The while loop makes it keep on asking until a valid input is<br>
received. Without the while loop it would only ask once and<br>
either return None or a digit.<br>
<br>
HTH<span class=""><br>
-- <br>
Alan G<br>
Author of the Learn to Program web site<br>
<a href="http://www.alan-g.me.uk/" target="_blank">http://www.alan-g.me.uk/</a><br>
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