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Hello and welcome to the Golang programming language course.

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In the previous session, we talked about A. In their face time and in this session, we want to talk

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about the others interface concept.

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Access underlying variable of interface down the line variable can be accessed in two ways.

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First type assertion and second type switch.

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Type assertion provides a way to access the underlying variable inside the inner face value of the interface

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by asserting the correct type of underlying value and types, which enables us to do above time assertion

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in serious.

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Type assertions.

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In Go language type assertion is an operation applied to the value of the interface or in other wars,

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time assertion is a process to extract the values of the interface.

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Now you can see the syntax.

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Here is the value of the expression of the interface and tee off her case is the type also known as

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assault type.

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The time assertion is used to check that the dynamic time of its operation will match the asserted type

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or not.

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If the tea is of concrete time, then the type assertion checks the given dynamic time of a is equal

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to the tea here.

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If the checking process is successfully, then the type assertion returns the dynamic value of a.

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Or if the checking fails, then the operation will panics.

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If the tea is of any interface time, then the time assertion checks the given dynamic time of a satisfying

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tea.

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Here, if the checking process successfully, then the dynamic value is not extracted.

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Now let's go to Vet School program to illustrate how to use the time ASUSTOR.

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First, define a function that accept the parameter as an empty interface.

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For example, a funk display, a medieval as an interface.

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Now, extracting the value of a and different type of a valuable for the example, in this case, visit

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Eastern Time for a better value column equals a don't walk in and close Frances's and define.

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This stream now display the value if p value, O'Connor says, value, the value will now go to main

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function and involve the display function and plus the arguments as extreme to it.

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First, define a string variable and initialize it that result.

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He called and said, well, you go through your own language.

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Now called the display function and send the result of a tweet display who said there isn't real reform

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at the code, save the project and execute the program.

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Now we can see the output value.

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Colin, go programming language.

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First, they define the function that accept a parameter as an empty interface and assign a string time

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to it.

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Then come the function and post a string value as argument to it and see the result.

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In this example, if we change the value type of value variable from string to E., then the program

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punch.

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Now check this problem.

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We change the value of result into an integer for the example.

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123 save the project and execute the program again.

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Now we can see the arrows.

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So we want to overcome this problem.

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First to the last quote.

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Save the project and read it right?

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First, define a function that accept an argument as an empty interface, a game for the example on

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display set variable A. as A. Interface

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go to the body.

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OK, now extracting the value of a and different type of a value.

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For the example, in this case, we set extreme time for a variable and assign it to two variables like

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value and value comma.

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OK column equals a don't open and close parenthesis and set a string as a tie.

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Now display the value.

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If if when you call in person.

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The.

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Status is percent v and calm here and sets venue and Oak Valley event here.

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If the time of the day is equal to that string, then the venue contains the dynamic venue of the A

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and okay will set to true.

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And if the time of the air is not equal to a string, then auto is set to false and the venue contains

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zero venue and the program does not punch.

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Now go to main function and invoke the display function and post the arguments to eat.

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First, define issuing variable and initialize each line.

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Result equals go through your own language and call the display function and sent the result variable

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to eat.

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Display city resolved by data OK.

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And second, define an integer variable and initialize it.

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Go to the next line that results two equals.

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Follow the example one hundred and twenty three and call display function and sent the result to variable

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to eat, display and set the result variable to reformat the code.

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Save the project and execute the program.

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Now we can see the output value for string is go programming language and its titles, its true and

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value for integer is zero and the phantoms is false.

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In this case, for the extreme time, watching variable contains through value and for the entire time,

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watching variable contains false value, and it does not given at all.

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In order not to prolong the time of decision, we would finish it and we will continue the content in

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the next session.

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Goodbye.