Let’s imagine that your (geeky) spouse has written a grocery list into a Perl array<\/a>. However, you don’t know if she’s included olive oil. You write a little program to read the array, then report if “olive oil” is present. <\/p>\n One extra parameter: your spouse likes to abbreviate. Therefore, she might have written “olive o.” for “olive oil.”<\/p>\n Here’s the program. Note that the comments<\/a> are in green<\/span>. perl groclist.txt<\/span><\/p>\n Assuming no typos (by me or you), you might be greeted with the following output:<\/p>\n
\nBack in my last post<\/a> I introduced the if, else<\/span> construction. Today we’ll look at a sample program that implements it.<\/p>\n
\n
\n#!\/usr\/bin\/perl<\/span>
\n
\n#for our purposes, you might imagine you can’t see the
#contents of @groceries<\/span>
\n@groceries=(“butter”,”sugar”,”bread”,”eggs”,”deli ham”,”cheddar cheese”,”olive oil”,”coffee”,”oranges”,”apples”,”grapes”,”olive o.”,”milk”,”cream”);
\n$i=0;
\nwhile($groceries[$i]){
\nif($groceries[$i] eq “olive oil”){
\nprint “Olive oil is element $i in the list.\\n”;
\n}
\nelsif($groceries[$i] eq “olive o.”){
\nprint “Olive o. is element $i in the list.\\n”;
\n}
\nelse{
\nprint “Not element $i\\n”;
\n}
\n$i++;
\n}
\n<\/span>
\nLet’s imagine this program is called groclist.txt<\/span>. On the command line, in its proper directory, you’d run it by keying in<\/p>\n
\nNot element 0
\nNot element 1
\nNot element 2
\nNot element 3
\nNot element 4
\nNot element 5
\nOlive oil is element 6 in the list.
\nNot element 7
\nNot element 8
\nNot element 9
\nNot element 10
\nOlive o. is element 11 in the list.
\nNot element 12
\nNot element 13
\n<\/span>
\n
\nThe details of this program I’ll explain next post. Cheers:)<\/p>\n