Removing Elements without Storing Them - Perl

We left off covering the splice() function, which can be used for adding and removing elements from a list. We also spoke about four other functions: pop(), push(), shift(), and unshift(), which are all similar to the splice() function, just not as flexible. In this article, we'll start out by discussing the splice() function in more detail, and learning how to remove more than one element in a list.

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By: James Payne

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March 31, 2008

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You might not wish to store the elements you removed while using splice(). It takes up memory, and can equate to more code and variables floating around than you really want. Here is how you remove elements without storing them:

#!/usr/bin/perl

@KoolAidFlavors = (@KoolAidFlavors, 'Grape ','Cherry ','Watermelon

','Fruit-Punch ','Orange ');

print @KoolAidFlavors;

print "\n\n";

splice(@KoolAidFlavors, 1,2);

print @KoolAidFlavors;

print "\n\n";

Here we create the @KoolAidFlavors list and add values to it. Next we print out the list, then use splice() to remove the two elements that follow the first element. Finally we print @KoolAidFlavors again, showing that we extracted some data from it. Here is the result:

Grape Cherry Watermelon Fruit-Punch Orange

Grape Fruit-Punch Orange

You can also remove items using a null list:

#!/usr/bin/perl

@KoolAidFlavors = (@KoolAidFlavors, 'Grape ','Cherry ','Watermelon

','Fruit-Punch ','Orange ');

print @KoolAidFlavors;

print "\n\n";

splice(@KoolAidFlavors, 1,2,());

print @KoolAidFlavors;

print "\n\n";

Which gives us the same result as above.