Difference between revisions of "PERL/C2/Functions-in-Perl/English-timed"

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{| border=1
 
{| border=1
−
!  <center>'''Time'''</center>
+
|'''Time'''
−
!  <center>'''Narration'''</center>
+
|'''Narration'''
 
   
 
   
 
|-
 
|-
−
| 00.01
+
| 00:01
−
|Welcome to the spoken tutorial on ''' Functions in Perl'''.
+
|Welcome to the spoken tutorial on ''' Functions in PERL'''.
  
 
|-
 
|-
−
| 00.06
+
| 00:06
−
| In this tutorial, we will learn about -
+
| In this tutorial, we will learn about:
  
 
|-
 
|-
−
|00.10
+
|00:10
−
|''' Perl functions '''
+
| PERL '''functions''', '''functions''' with '''arguments'''
 
   
 
   
 
|-
 
|-
−
|00.11
+
|00:13
−
| ''' functions''' with '''arguments '''
+
|'''functions''' with '''return values'''.
−
+
−
|-
+
−
|00.13
+
−
|''' function''' with '''return values'''  
+
  
 
|-
 
|-
−
|00.16
+
|00:16
−
|For this tutorial, I am using  
+
|For this tutorial, I am using:
 
   
 
   
 
|-
 
|-
−
| 00.18
+
| 00:18
−
| ''' Ubuntu Linux12.04''' operating system  
+
|'''Ubuntu Linux 12.04''' operating system  
  
 
|-
 
|-
−
| 00.22
+
| 00:22
 
|''' Perl 5.14.2''' and  
 
|''' Perl 5.14.2''' and  
  
 
|-
 
|-
−
| 00.24
+
| 00:24
−
| ''' gedit''' Text Editor  
+
|''' gedit''' Text Editor.
  
 
|-
 
|-
−
|00.27
+
|00:27
 
|You can use any text editor of your choice.  
 
|You can use any text editor of your choice.  
 
   
 
   
 
|-
 
|-
−
|00.31
+
|00:31
−
|You should have basic knowledge of ''' variables, comments, loops, conditional statements''' and ''' Data Structures''' in '''Perl.'''
+
|You should have basic knowledge of ''' variables, comments, loops, conditional statements''' and '''data Structures''' in PERL.
 
   
 
   
 
|-
 
|-
−
| 00.41
+
| 00:41
−
| Please go through the relevant spoken tutorials on the ''' spoken tutorial''' website.   
+
| Please go through the relevant spoken tutorials on the '''Spoken Tutorial''' website.   
 
   
 
   
 
|-
 
|-
−
|00.47
+
|00:47
−
|We will first see some simple ''' Perl functions.'''
+
|We will first see some simple PERL''' functions.'''
  
−
 
 
|-
 
|-
−
|00.51
+
|00:51
−
|In ''' Perl, functions''', also called as ''' subroutines''', are declared with ''' sub keyword.'''
+
|In PERL, '''functions''', also called as ''' subroutines''', are declared with '''sub''' keyword.
−
 
+
  
 
|-
 
|-
−
| 00.57
+
| 00:57
−
| The definition of a declared ''' function''' is written between curly braces.  
+
| The definition of a declared function is written between curly braces.  
  
 
|-
 
|-
−
|01.03
+
|01:03
−
|This ''' function''' does not take any ''' arguments.'''  
+
|This function does not take any ''' arguments.'''  
  
 
|-
 
|-
−
|01.07
+
|01:07
 
| And, it does not return anything.  
 
| And, it does not return anything.  
 
   
 
   
 
|-
 
|-
−
|01.10
+
|01:10
−
|Note: ''' function''' definition can be written anywhere in the script or in another '''module'''.  
+
|Note: function definition can be written anywhere in the script or in another '''module'''.  
  
 
|-
 
|-
−
|01.17
+
|01:17
−
|This ''' module''', must then be included in the script, to use this ''' function.'''
+
|This '''module''' must then be included in the script, to use this function.  
 
   
 
   
 
|-
 
|-
−
|01.24
+
|01:24
−
|To include the ''' module ''' file in the script, one has to use the following syntax-
+
|To include the '''module''' file in the script, one has to use the following syntax:
  
−
 
 
|-
 
|-
−
|01.31
+
|01:31
−
| ''' use ModuleFileName semicolon '''
+
| ''' use ModuleFileName''' semicolon
−
 
+
 
   
 
   
 
|-
 
|-
−
| 01.35
+
| 01:35
 
|Let us understand this using a sample program.  
 
|Let us understand this using a sample program.  
  
 
|-
 
|-
−
|01.39
+
|01:39
−
|Open a file in your text editor and name it as ''' simpleFunction dot pl'''
+
|Open a file in your text editor and name it as '''simpleFunction dot pl'''.
 
   
 
   
 
|-
 
|-
−
|01.46
+
|01:46
 
| Here is my ''' simpleFunction dot pl'''  file in '''gedit.'''  
 
| Here is my ''' simpleFunction dot pl'''  file in '''gedit.'''  
−
 
  
 
|-
 
|-
−
| 01.51
+
| 01:51
 
| Type the code as displayed on the screen.  
 
| Type the code as displayed on the screen.  
 
   
 
   
 
|-
 
|-
−
|01.55
+
|01:55
−
|Here, we are just calling a ''' function''', which we have defined.  
+
|Here, we are just calling a function which we have defined.  
−
+
 
−
+
 
|-
 
|-
−
|02.00
+
|02:00
−
|Then, the execution control is passed to that ''' function.'''
+
|Then the execution control is passed to that function.
−
 
+
 
   
 
   
 
|-
 
|-
−
|02.06
+
|02:06
−
|This is the declaration & definition of the ''' function.'''
+
|This is the declaration & definition of the function.  
 
   
 
   
 
|-
 
|-
−
|02.10
+
|02:10
−
|This ''' function''' will print out the given text.  
+
|This function will print out the given text.  
  
−
 
 
|-
 
|-
−
|02.14
+
|02:14
 
|Save your file.  
 
|Save your file.  
  
 
|-
 
|-
−
|02.17
+
|02:17
−
|Then switch to the terminal and execute the ''' Perl script''' by typing  
+
|Then switch to the terminal and execute the PERL '''script''' by typing:
  
 
|-
 
|-
−
|02.24
+
|02:24
−
|''' perl simpleFunction dot pl'''
+
|'''perl simpleFunction dot pl'''
  
 
|-
 
|-
−
|02.28
+
|02:28
 
|and press '''Enter.'''
 
|and press '''Enter.'''
 
   
 
   
 
|-
 
|-
−
|02.30
+
|02:30
−
|The output will be as shown on the terminal
+
|The output will be as shown on the terminal.
  
 
|-
 
|-
−
|02.38
+
|02:38
−
|Now, let us see a ''' function''' with '''arguments.'''
+
|Now, let us see a '''function''' with '''arguments'''.
−
 
+
 
   
 
   
 
|-
 
|-
−
|02.44
+
|02:44
 
|Let us understand this function using a sample program.  
 
|Let us understand this function using a sample program.  
−
 
 
   
 
   
 
|-
 
|-
−
| 02.48
+
|02:48
−
| Open a file in your text editor and name it as '''functionWithArgs dot pl'''
+
| Open a file in your text editor and name it as '''functionWithArgs dot pl'''.
 
   
 
   
 
|-
 
|-
−
|   02.57
+
|02:57
−
|Here is my ''' functionWithArgs''' script in '''gedit. '''
+
|Here is my '''functionWithArgs''' script in '''gedit. '''
−
+
  
 
|-
 
|-
−
| 03.02
+
|03:02
 
| Type the following piece of code as shown on the screen.  
 
| Type the following piece of code as shown on the screen.  
 
   
 
   
 
|-
 
|-
−
|03.07
+
|03:07
−
|Here, we are calling a function with ''' arguments, 10'''  and '''20'''.  
+
|Here, we are calling the '''function''' with arguments 10 and 20.  
 
   
 
   
 
|-
 
|-
−
| 03.13
+
| 03:13
−
| The passed '''arguments''' are caught in ''' $var1''' & ''' $var2.'''
+
| The passed arguments are caught in '$var1' & '$var2'.  
 
   
 
   
 
|-
 
|-
−
| 03.20
+
| 03:20
−
|@_ is a special '''Perl variable.''' We will cover its details in future tutorials.  
+
|'''@_''' is a special '''Perl''' variable. We will cover its details in future tutorials.  
−
 
+
  
 
|-
 
|-
−
|03.29
+
|03:29
−
|This '''function''' performs the addition of 2 '''variables''' and prints the answer.  
+
|This function performs the addition of 2 variables and prints the answer.  
 
   
 
   
 
|-
 
|-
−
|03.37
+
|03:37
 
|Save your file.  
 
|Save your file.  
−
+
 
−
+
 
|-
 
|-
−
| 03.42
+
|03:42
−
| ''' @_ '''is a special Perl array.  
+
| '''@_'''is a special '''Perl''' array.  
−
 
+
 
   
 
   
 
|-
 
|-
−
|03.46
+
|03:46
−
|This ''' array''' is used to store the passed '''arguments'''.  
+
|This array is used to store the passed arguments.   
−
   
+
 
   
 
   
 
|-
 
|-
−
| 03.51
+
|03:51
−
| Similarly, we can catch the passed ''' arguments''' in ''' variables''' as  
+
| Similarly, we can catch the passed arguments in variables as:
  
 
|-
 
|-
−
|   03.56
+
|03:56
−
| ''' $var1 space = space  shift @_ semicolon'''
+
|'''$var1 space = space  shift @_''' semicolon
−
 
+
 
   
 
   
 
|-
 
|-
−
| 04.04
+
|04:04
−
|''' $var2 space  = space  shift @_ semicolon'''
+
|'''$var2 space  = space  shift @_''' semicolon
  
−
 
 
|-
 
|-
−
| 04.12
+
| 04:12
−
| '''shift @_ removes the element at first position from @_ array '''
+
| '''shift @_''' removes the element at first position from '''@_ array '''
  
 
|-
 
|-
−
| 04.21
+
| 04:21
−
| and assigns it to a ''' variable '''
+
| and assigns it to a variable.
−
 
+
  
 
|-
 
|-
−
|04.24
+
|04:24
−
|Another way is; ''' $var1 space  =  space dollar underscrore open square bracket zero close square bracket semicolon '''
+
|Another way is: '''$var1 space  =  space dollar underscore open square bracket zero close square bracket''' semicolon.
  
 
|-
 
|-
−
|04.38
+
|04:38
−
| ''' $var2 space  =  space dollar underscrore open square bracket 1 close square bracket semicolon'''
+
| '''$var2 space  =  space dollar underscore open square bracket 1 close square bracket''' semicolon.
 
   
 
   
 
|-
 
|-
−
|04.49
+
|04:49
−
|The above mentioned way is similar to fetching ''' elements''' of '''@_ array''' using '''index.'''
+
|The above mentioned way is similar to the fetching '''elements''' of '''@_ array''' using '''index.'''
−
 
+
  
 
|-
 
|-
−
|04.59
+
|04:59
−
|Now, switch to terminal and execute the script by typing -
+
|Now, switch to '''terminal''' and execute the '''script''' by typing:
  
 
|-
 
|-
−
|05.06
+
|05:06
−
|''' perl functionWithArgs dot pl''' and press '''Enter '''
+
|''' perl functionWithArgs dot pl''' and press '''Enter '''.
−
 
+
  
 
|-
 
|-
−
|05.14
+
|05:14
−
|The output is as displayed on the screen
+
|The output is as displayed on the screen.
 
   
 
   
 
|-
 
|-
−
| 05.23
+
| 05:23
−
| Now, let us look at a '''functions''' which returns a single value.  
+
| Now, let us look at a function which returns a single value.  
  
−
 
 
|-
 
|-
−
|05.32
+
|05:32
−
|Let us understand the same using a sample program.  
+
|Let us understand the same, using a sample program.  
  
 
|-
 
|-
−
|05.35
+
|05:35
−
|Let me switch to ''' funcWithSingleRtrnVal dot pl ''' script in '''gedit.'''
+
|Let me switch to '''funcWithSingleRtrnVal dot pl''' script in '''gedit.'''
 
   
 
   
 
|-
 
|-
−
|05.46
+
|05:46
 
|Open a file in your text editor and type the following piece of code as shown.
 
|Open a file in your text editor and type the following piece of code as shown.
 
   
 
   
 
|-
 
|-
−
|05.52
+
|05:52
−
|Here, we are calling ''' addVariables function''' with '''parameters''' 10 and 20.  
+
|Here, we are calling ''' addVariables''' function with '''parameters''' 10 and 20.  
 
   
 
   
 
|-
 
|-
−
|06.01
+
|06:01
−
|The return value of the ''' function''' is caught in ''' $addition variable.'''
+
|The return value of the function is caught in '$addition' variable.
  
 
|-
 
|-
−
|06.09
+
|06:09
−
|This function does the addition of the passed parameters and returns the answer.  
+
|This function does the addition of the passed '''parameters''' and returns the answer.  
  
−
 
−
 
 
|-
 
|-
−
|06.15
+
|06:15
−
|Save the file.  
+
|'''Save''' the file.  
−
 
+
 
   
 
   
 
|-
 
|-
−
|06.17
+
|06:17
−
|Now let us execute the script.  
+
|Now, let us '''execute''' the '''script'''.  
  
 
|-
 
|-
−
| 06.20
+
|06:20
−
|So, switch to terminal and type-
+
|So, switch to '''terminal''' and type:
  
 
|-
 
|-
−
| 06.24
+
|06:24
 
|''' perl funcWithSingleRtrnVal dot pl'''  and press '''Enter.'''  
 
|''' perl funcWithSingleRtrnVal dot pl'''  and press '''Enter.'''  
−
 
  
 
|-
 
|-
−
|06.35
+
|06:35
−
| The output is as displayed on the terminal.  
+
| The '''output''' is as displayed on the terminal.  
−
 
+
 
   
 
   
 
|-
 
|-
−
| 06.43
+
|06:43
 
| Now, let us see a function which returns multiple values.  
 
| Now, let us see a function which returns multiple values.  
−
 
 
   
 
   
 
|-
 
|-
−
| 06.48
+
|06:48
 
| Let us understand the same, using a sample program.  
 
| Let us understand the same, using a sample program.  
  
 
|-
 
|-
−
| 06.53
+
|06:53
−
| In gedit, I have opened a file and named it as ''' funcWithMultipleRtrnVals dot pl'''  
+
| In '''gedit''', I have opened a file and named it as ''' funcWithMultipleRtrnVals dot pl'''.
  
 
|-
 
|-
−
| 07.04
+
|07:04
−
|Please do like wise in your text editor
+
|Please do like-wise in your '''text editor'''.
 +
 
 
|-
 
|-
−
| 07.08
+
|07:08
 
| Now, type the following piece of code as shown.  
 
| Now, type the following piece of code as shown.  
  
 
|-
 
|-
−
|07.13
+
|07:13
 
|Here, we are calling '''addVariables''' function with parameters 10 and 20.
 
|Here, we are calling '''addVariables''' function with parameters 10 and 20.
 
   
 
   
 
|-
 
|-
−
| 07.21
+
|07:21
−
| The return values of the function are caught in variables ''' $var1, $var2 and  $addition'''  
+
| The return values of the function are caught in variables ''' $var1, $var2 and  $addition'''.
 
   
 
   
 
|-
 
|-
−
| 07.31
+
|07:31
 
| This function does the addition and returns the passed parameters and the resultant answer.  
 
| This function does the addition and returns the passed parameters and the resultant answer.  
  
 
|-
 
|-
−
|07.42
+
|07:42
−
|This illustration demonstrates how we can return an ''' array'''  from a '''function'''.
+
|This illustration demonstrates how we can return an array from a function.
−
 
+
−
|-
+
−
| 07.53
+
−
|Similarly, this demonstrates how ''' hash''' can be returned from a function.
+
−
 
+
  
 
|-
 
|-
−
|08.00
+
| 07:53
−
| Save your file.  
+
|Similarly, this demonstrates how '''hash''' can be returned from a function.  
  
 +
|-
 +
|08:00
 +
| '''Save''' your file.
  
 
|-
 
|-
−
|08.03
+
|08:03
−
| Now let us execute the ''' Perl''' script on the terminal by typing -
+
| Now let us execute the '''Perl''' script on the terminal by typing:
 
   
 
   
 
|-
 
|-
−
| 08.10
+
|08:10
 
| '''perl funcWithMultipleRtrnVals dot pl '''
 
| '''perl funcWithMultipleRtrnVals dot pl '''
  
 
|-
 
|-
−
| 08.18
+
| 08:18
 
| and press '''Enter.'''
 
| and press '''Enter.'''
  
 
|-
 
|-
−
| 08.20
+
|08:20
 
| The output is as displayed on the terminal.
 
| The output is as displayed on the terminal.
  
 
|-
 
|-
−
| 08.32
+
|08:32
−
|'''Perl'''  provides several '''inbuilt functions.'''
+
|'''Perl'''  provides several inbuilt functions.
  
−
 
 
|-
 
|-
−
|08.36
+
|08:36
−
| We learnt some of them in earlier tutorials. For eg- ''' Arrays, Hash, sort, scalar, each, keys''' etc.  
+
| We learnt some of them in earlier tutorials. For e.g- ''' arrays, Hash, sort, scalar, each, keys''' etc.  
 
   
 
   
 
|-
 
|-
−
|08.49
+
|08:49
−
|Calling '''inbuilt functions''', similar to calling any other function, which we define.  
+
|Calling inbuilt functions is similar to calling any other function which we define.  
  
 
|-
 
|-
−
|08.57
+
|08:57
−
|E.g ''' sort open bracket @arrayName close bracket semicolon'''
+
|e.g '''sort open bracket @arrayName close bracket''' semicolon.
 
 
 
 
 
|-
 
|-
−
|09.04
+
|09:04
−
| Try incorporating some ''' inbuilt functions''' in the sample programs we used.  
+
| Try incorporating some inbuilt functions in the sample programs we used.  
  
 
|-
 
|-
−
|09.10
+
|09:10
 
|And observe their outputs.  
 
|And observe their outputs.  
  
 
|-
 
|-
−
|09.13
+
|09:13
 
| Let us summarize.  
 
| Let us summarize.  
  
 
|-
 
|-
−
|09.15
+
|09:15
−
|In this tutorial, we have learnt -
+
|In this tutorial, we have learnt: 
 
   
 
   
 
|-
 
|-
−
|09.17
+
|09:17
−
|''' Functions in Perl'''  
+
|'''functions''' in '''Perl'''
  
 
|-
 
|-
−
|09.19
+
|09:19
−
| ''' functions''' with '''arguments''' and   
+
|'''functions''' with '''arguments''' and   
  
 
|-
 
|-
−
|09.22
+
|09:22
−
|''' functions''' which '''return values''' using sample programs.  
+
| '''functions''' which return values using sample programs.  
  
 
|-
 
|-
−
|09.27
+
|09:27
−
|Here is assignment for you -
+
|Here is an assignment for you: 
  
 
|-
 
|-
−
|09.29
+
|09:29
−
|Write a '''function''' which takes 3 '''arguments. '''
+
|Write a '''function''' which takes 3 '''arguments.'''
  
 
|-
 
|-
−
|09.33
+
|09:33
−
|Perform some action on these '''arguments '''
+
|Perform some action on these '''arguments'''.
  
 
|-
 
|-
−
|09.37
+
|09:37
−
|Return the result of the action performed on the '''arguments''' and print the same.  
+
|'''Return''' the result of the action performed on the '''arguments''' and print the same.  
−
 
+
  
 +
|-
 +
|09:43
 +
|Watch the video available at the following link.
  
 
|-
 
|-
−
|09.43
+
|09:47
−
|Watch the video available at the following link
+
|It summarizes the Spoken Tutorial project.
−
+
 
   
 
   
 
|-
 
|-
−
|09.47
+
|09:51
−
|It summaries the Spoken Tutorial project
+
|If you do not have good bandwidth, you can download and watch it.
−
+
 
   
 
   
 
|-
 
|-
−
|09.51
+
| 09:56
−
|If you do not have good bandwidth, you can download and watch it
+
| The Spoken Tutorial project team: * Conducts workshops using spoken tutorials.
 
   
 
   
 
|-
 
|-
−
| 09.56
+
|10:02
−
| The Spoken Tutorial Project Team  Conducts workshops using spoken tutorials
+
|Gives certificates to those who pass an online test.
−
+
 
   
 
   
 
|-
 
|-
−
|10.02
+
|10:07
−
|Gives certificates to those who pass an online  test
+
|For more details, please write to: contact at spoken hyphen tutorial dot org.
 
   
 
   
 
|-
 
|-
−
|10.07
+
| 10:14
−
|For more details, please write to contact at spoken hyphen tutorial dot org
+
| "Spoken Tutorial" project is a part of the "Talk to a Teacher" project.
 
   
 
   
 
|-
 
|-
−
| 10.14
+
|10:19
−
|  Spoken Tutorial Project is a part of the Talk to a  Teacher project
+
−
+
−
+
−
|-
+
−
|10.19
+
 
|It is supported by the National Mission on Education through ICT, MHRD, Government of India.
 
|It is supported by the National Mission on Education through ICT, MHRD, Government of India.
−
 
 
   
 
   
 
|-
 
|-
−
|10.28
+
|10:28
−
|More information on this Mission is available at spoken hyphen tutorial dot org slash NMEICT hyphen Intro
+
|More information on this mission is available at: spoken hyphen tutorial dot org slash NMEICT hyphen Intro.
 
   
 
   
 
|-
 
|-
−
| 10.40
+
| 10:40
−
| Hope you enjoyed this Perl tutorial.  
+
| Hope you enjoyed this '''Perl''' tutorial.  
 
   
 
   
 
|-
 
|-
−
|10.43
+
|10:43
−
|This is Amol signing off.
+
|This is Amol, signing off.
−
+
 
   
 
   
 
|-
 
|-
−
|10.46
+
|10:46
 
|Thanks for joining.
 
|Thanks for joining.
 
   
 
   
 
|}
 
|}

Latest revision as of 15:52, 10 March 2017

Time Narration
00:01 Welcome to the spoken tutorial on Functions in PERL.
00:06 In this tutorial, we will learn about:
00:10 PERL functions, functions with arguments
00:13 functions with return values.
00:16 For this tutorial, I am using:
00:18 Ubuntu Linux 12.04 operating system
00:22 Perl 5.14.2 and
00:24 gedit Text Editor.
00:27 You can use any text editor of your choice.
00:31 You should have basic knowledge of variables, comments, loops, conditional statements and data Structures in PERL.
00:41 Please go through the relevant spoken tutorials on the Spoken Tutorial website.
00:47 We will first see some simple PERL functions.
00:51 In PERL, functions, also called as subroutines, are declared with sub keyword.
00:57 The definition of a declared function is written between curly braces.
01:03 This function does not take any arguments.
01:07 And, it does not return anything.
01:10 Note: function definition can be written anywhere in the script or in another module.
01:17 This module must then be included in the script, to use this function.
01:24 To include the module file in the script, one has to use the following syntax:
01:31 use ModuleFileName semicolon
01:35 Let us understand this using a sample program.
01:39 Open a file in your text editor and name it as simpleFunction dot pl.
01:46 Here is my simpleFunction dot pl file in gedit.
01:51 Type the code as displayed on the screen.
01:55 Here, we are just calling a function which we have defined.
02:00 Then the execution control is passed to that function.
02:06 This is the declaration & definition of the function.
02:10 This function will print out the given text.
02:14 Save your file.
02:17 Then switch to the terminal and execute the PERL script by typing:
02:24 perl simpleFunction dot pl
02:28 and press Enter.
02:30 The output will be as shown on the terminal.
02:38 Now, let us see a function with arguments.
02:44 Let us understand this function using a sample program.
02:48 Open a file in your text editor and name it as functionWithArgs dot pl.
02:57 Here is my functionWithArgs script in gedit.
03:02 Type the following piece of code as shown on the screen.
03:07 Here, we are calling the function with arguments 10 and 20.
03:13 The passed arguments are caught in '$var1' & '$var2'.
03:20 @_ is a special Perl variable. We will cover its details in future tutorials.
03:29 This function performs the addition of 2 variables and prints the answer.
03:37 Save your file.
03:42 @_is a special Perl array.
03:46 This array is used to store the passed arguments.
03:51 Similarly, we can catch the passed arguments in variables as:
03:56 $var1 space = space shift @_ semicolon
04:04 $var2 space = space shift @_ semicolon
04:12 shift @_ removes the element at first position from @_ array
04:21 and assigns it to a variable.
04:24 Another way is: $var1 space = space dollar underscore open square bracket zero close square bracket semicolon.
04:38 $var2 space = space dollar underscore open square bracket 1 close square bracket semicolon.
04:49 The above mentioned way is similar to the fetching elements of @_ array using index.
04:59 Now, switch to terminal and execute the script by typing:
05:06 perl functionWithArgs dot pl and press Enter .
05:14 The output is as displayed on the screen.
05:23 Now, let us look at a function which returns a single value.
05:32 Let us understand the same, using a sample program.
05:35 Let me switch to funcWithSingleRtrnVal dot pl script in gedit.
05:46 Open a file in your text editor and type the following piece of code as shown.
05:52 Here, we are calling addVariables function with parameters 10 and 20.
06:01 The return value of the function is caught in '$addition' variable.
06:09 This function does the addition of the passed parameters and returns the answer.
06:15 Save the file.
06:17 Now, let us execute the script.
06:20 So, switch to terminal and type:
06:24 perl funcWithSingleRtrnVal dot pl and press Enter.
06:35 The output is as displayed on the terminal.
06:43 Now, let us see a function which returns multiple values.
06:48 Let us understand the same, using a sample program.
06:53 In gedit, I have opened a file and named it as funcWithMultipleRtrnVals dot pl.
07:04 Please do like-wise in your text editor.
07:08 Now, type the following piece of code as shown.
07:13 Here, we are calling addVariables function with parameters 10 and 20.
07:21 The return values of the function are caught in variables $var1, $var2 and $addition.
07:31 This function does the addition and returns the passed parameters and the resultant answer.
07:42 This illustration demonstrates how we can return an array from a function.
07:53 Similarly, this demonstrates how hash can be returned from a function.
08:00 Save your file.
08:03 Now let us execute the Perl script on the terminal by typing:
08:10 perl funcWithMultipleRtrnVals dot pl
08:18 and press Enter.
08:20 The output is as displayed on the terminal.
08:32 Perl provides several inbuilt functions.
08:36 We learnt some of them in earlier tutorials. For e.g- arrays, Hash, sort, scalar, each, keys etc.
08:49 Calling inbuilt functions is similar to calling any other function which we define.
08:57 e.g sort open bracket @arrayName close bracket semicolon.
09:04 Try incorporating some inbuilt functions in the sample programs we used.
09:10 And observe their outputs.
09:13 Let us summarize.
09:15 In this tutorial, we have learnt:
09:17 functions in Perl
09:19 functions with arguments and
09:22 functions which return values using sample programs.
09:27 Here is an assignment for you:
09:29 Write a function which takes 3 arguments.
09:33 Perform some action on these arguments.
09:37 Return the result of the action performed on the arguments and print the same.
09:43 Watch the video available at the following link.
09:47 It summarizes the Spoken Tutorial project.
09:51 If you do not have good bandwidth, you can download and watch it.
09:56 The Spoken Tutorial project team: * Conducts workshops using spoken tutorials.
10:02 Gives certificates to those who pass an online test.
10:07 For more details, please write to: contact at spoken hyphen tutorial dot org.
10:14 "Spoken Tutorial" project is a part of the "Talk to a Teacher" project.
10:19 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
10:28 More information on this mission is available at: spoken hyphen tutorial dot org slash NMEICT hyphen Intro.
10:40 Hope you enjoyed this Perl tutorial.
10:43 This is Amol, signing off.
10:46 Thanks for joining.

Contributors and Content Editors

Gaurav, PoojaMoolya, Sandhya.np14

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