Perl Tutorial - 46: Working with Arguments Video Lecture | Perl Building Blocks: An Introduction to Perl - Back-End Programming

hello guys welcome to my channel this is
the 46th tutorial in this course and in
this tutorial we will check out another
application of subroutines in Perl so as
you can see I have a script opened up
here it's called character underscore
split and in this tutorial in this
script I am going to create a subroutine
and then I am going to pass a bunch of
characters to it and that bunch is going
to have some lowercase alphabets some
uppercase alphabets it's gonna have some
digits and it's also gonna have some
special characters and then I am going
to use the code in the subroutine to
segregate the uppercase alphabets from
the lowercase alphabets and you know I
would separate the digits as well as
except special characters and then I
would display them separately so the
name of the subroutine is char works and
I have created it on line number 3 using
the sub keyword and then on line number
4 I have the opening curly brace for the
subroutine and line line number 28 I
have the corresponding closing curly
brace and then I have made a call to the
subroutine on line number 29 and you
make the call by just typing in the name
of the subroutine and that in this case
is char works and then as I said I have
passed a bunch of characters you have
small ABC and then you have the dollar
symbol the pound symbol ampersand and
then you have the asterisk and then you
have uppercase s are T and we and then
you have some digits eight one three
five four seven six so the idea is to
separate the lowercase alphabets from SR
TV and then the special characters from
the rest of the characters and then the
digits have to be displayed separately
so the four kinds of characters have to
be classified into four different bins
and then they have to be displayed so
when you pass you know string of
characters or even if your arguments are
entirely numeric as I mentioned in the
last tutorial the arguments are
collected by the subroutine in the form
of us
list which you can access using the add
the rate symbol in the underscore symbol
so we are going to use a for each loop
which is gonna have a scalar variable C
as its control variable and then we're
gonna loop through the contents of you
know the argument list the you know the
arguments that are passed to this
particular subroutine so that is
contained in this list so when you have
a statement like this you're going to
loop through the contents of the
characters that have been passed through
in the first iteration the scalar
variable C is going to hold small a in
the second iteration it's going to hold
small B in the third iteration it's
going to hold small C so on and so forth
so within the for each loop we're gonna
check if the ask I code of the character
that has been passed is greater than
equal to 65 and less than equal to 90 or
not if that is the case then it means
it's an uppercase alphabet because the
ask I code for capital a uppercase a is
65 and that of capital Z is 90 so in
perl i don't remember if i have
mentioned this earlier in this course or
not but you check the ask i code of a
character using the Ord function so you
type Ord and then within parentheses you
pass dollar C which is the variable
that's going to hold the character from
this list and you check if the ask I
value is within this range or not if
that is the case and you use the push
function to store the character in a
list called upper right so this list has
been created to hold all the uppercase
alphabets and you created obviously
using the add the ride cymbal and if the
ask I quote does not lie in this range
then we're gonna check if it lies in
another range which is 97 to 122 and
this range 97 222 is for lowercase
alphabets so if the ASCII value falls in
this range and we're going to append the
character to another list called lower
and again
using the push function for this and if
it does not lie in this range either
then we're gonna check if it lies
between 48 and 57 and that's the case
then it is a digit so again I'm using
the already function to fetch the asked
I chord and then I'm you know simply
using the push function to push the
character to another list called digits
and if it does not lie in any of these
three ranges and it means it's a special
character so we don't need a condition
here you could just use the else block
to you know pass the character to the
list called special using the push
function so after doing all this after
for each has completed all its
hydrations we're going to get to line
number 24 where I have a print statement
to display the uppercase alphabets so
we're gonna first show the text
uppercase alphabets passed colon then
we're going to display all the values
from this character list there are
uppercase alphabets and then similarly I
have print statements for lowercase
alphabets for digits as well as for
special special characters past I'll
make sure this file saved and when I
press f5 I see that the uppercase
alphabets past our SRT and we and the
lowercase alphabets past are a b and c
and then the digits passed are 8 1 3 5 4
7 6 and the special characters passed
our dollar symbol pound symbol ampersand
and the asterisk so it has successfully
segregated all characters and it is
classified in the correct bins and it
has displayed the for less correctly as
well so I hope you guys had fun watching
this tutorial you may subscribe to my
channel if you haven't already I'm going
to see you in the next video in which we
continue our discussion on Perl and
thanks for watching this one as you soon
till then take care