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Question: What is the purpose of the chomp function in Perl?
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Answer: The 'chomp' function in Perl is used to remove the newline character (\n) from the end of a string.
It is commonly used when reading input from a file or from the standard input (STDIN).
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Question: What is the purpose of the 'undef' function in Perl?
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Answer: The 'undef' function in Perl is used to remove the value from a variable, effectively making it undefined.
It can be used to reset a variable to an undefined state or to free memory associated with a variable.
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Question: Can you explain the difference between grep and map in Perl?
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Answer: Please find below the difference:
• 'grep' is used to filter elements from a list based on a given condition. It returns a new list containing elements that satisfy the condition.
• 'map' is used to transform elements of a list according to a specified transformation. It returns a new list containing the results of applying the transformation to each element.
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Question: What are regular expressions in Perl?
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Answer: The regular expressions in Perl are patterns used for matching and manipulating text.
They provide a powerful and flexible way to search for and extract specific patterns of characters within strings.
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Question: How do you declare and use a hash in Perl?
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Answer: Hashes are declared using the % sigil. You can assign key-value pairs to hash using => operator
or by separating key-value with a comma.
To access the value associated with a key, you use the key inside curly braces ({}).
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Question: How do you handle file I/O errors in Perl?
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Answer: File I/O errors in Perl can be handled using the die function along with the $! variable,
which contains the system error message associated with the last system call.
You can also use eval to trap exceptions and handle errors gracefully.
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Question: Can you explain the concept of autovivification in Perl?
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Answer: The autovivification is a feature in Perl where data structures (such as arrays or hashes)
are automatically created when they are accessed or assigned to, even if they don't exist yet.
This can lead to unexpected behavior if not understood properly.
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Question: What is a Perl package, and how do you create one?
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Answer: A Perl package is a namespace that contains variables, subroutines, and other symbols.
You can create a package using the package keyword followed by the package name.
Variables and subroutines declared within the package are accessible using the package name as a prefix.
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Question: Can you explain the difference between 'shift' and 'unshift' in Perl?
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Answer: You can find the difference below:
• 'shift' removes and returns the first element of an array, shifting all other elements down.
• 'unshift' adds one or more elements to the beginning of an array, shifting existing elements to higher indices.
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