Difference between revisions of "PERL/C2/Conditional-statements/English-timed"

|Welcome to the spoken tutorial on '''if and if-else conditional statements''' in '''Perl'''.

|* '''if ''' statement and  

|* ''' if-else''' statement in Perl.  

   

| I am using '''Ubuntu Linux 12.04''' operating system and '''Perl 5.14.2'''.

|Please go through the relevant spoken tutorials on the '''spoken tutorial''' website.  

|* '''if'''

   

|* '''if-else '''

|* '''if-elsif-else''' and  

|* '''switch '''.

|In this tutorial, we will cover '''if '''and '''if-else''' statements.  

|'''if '''space open bracket '''condition''' close bracket space Open curly bracket  

|'''Enter'''

|Piece of code semicolon,  to be executed when the condition is true   

| '''Enter''', Close curly bracket

|The code inside the '''if''' statement will be executed only when the condition is true.  

| Now let us look at an example of '''if ''' statement.  

|Open the Terminal and type  

|'''gedit conditionalBlocks dot pl ''' space '''&'''(ampersand )

|and press '''Enter'''

|This will open the '''conditionalBlocks.pl''' file in gedit.  

|Here we have specified a condition for '''if''' which checks the value of variable count.  

| Note the '''equal to equal to''' sign here. This is the '''comparison''' operator.  

|The condition '''$count equal to equal to 5 ''' is checked against the value of variable count.  

|Type the following to check for any compilation or syntax error -

| and press '''Enter. '''

|The following line will be displayed on the terminal window   

| '''conditionalBlocks.pl syntax OK '''

|   03:04

| As there is no compilation or syntax error, we will execute the Perl script by typing -

| and press '''Enter'''

| ''' I am inside if statement'''

|Switch back to gedit

|Alternately, we can write the above ''' if''' statement as-

|'''print ''' space double quotes '''I am inside if statement''' slash '''n''' close double quotes space '''if''' open bracket '''dollar count space equal to equal to space 5''' close bracket semicolon.

| 03:57

|This statement is used when user wants to execute  

|one piece of code when the condition is true and  

| 04:09

| another piece of code when the condition is false

|   04:13

| The syntax for '''if-else''' condition is as follows -

| 04:17

| 04:27

| 04:29

| to be executed when '''if''' condition is true,  

|Press '''Enter '''

|to be executed when if condition is false  

|Press '''Enter''' close curly bracket  

| Now again, go to the '''conditionalBlocks.pl''' file which we have already created in gedit.  

| Assign 4 to count variable then at the end of the if block type space  

| ''' else '''

|'''print''' space double quotes '''I am inside else statement slash n''' close double quotes semicolon  

|Press '''Enter''' and close '''curly bracket.'''

|Here, '''4''' is assigned to variable '''$count. '''

| 05:56

| 06:11

| Now, press '''Enter'''.

| 06:13

| The following line will be displayed on the terminal:  

| 06:17

| "conditionalBlocks.pl syntax OK"

| 06:20

|As there is no compilation or syntax error, we will now execute the Perl script.  

| 06:33

| and press '''Enter'''.

| 06:35

|'''if''' and  

|'''if-else''' conditional statements in Perl  

| Print “It is an open source language”

|It summaries the Spoken Tutorial project.

| The Spoken Tutorial project Team:  

| Conducts workshops using spoken tutorials.

|Gives certificates to those who pass an online test.