Scalars, Arrays, and Hashes in Perl

Jan 7, 2015

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This chapter is from the book 

Perl by Example, 5th Edition

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5.5 What You Should Know

If you don’t give a variable a value, what will Perl assign to it?
What are “funny characters”? What is a sigil?
What data types are interpreted within double quotes?
How many numbers or strings can you store in a scalar variable?
In a hash, can you have more than one key with the same name? What about more than one value with the same name?
What function would you use to find the index value of an array if you know the value of the data stored there?
How does the scalar function evaluate an expression if it’s an array?
How do you find the size of an array?
What does the $” special variable do?
When are elements of an array or hash preceded by a $ (dollar sign)?
What is the difference between chop and chomp?
What is the difference between splice and slice?
What does the map function do?
How do you sort a numeric array? How do you sort a hash by value?
What function extracts both keys and values from a hash?
How can you remove duplicates in an array?
What is meant by the term scope?
What is “scalar” context, “list” context, “void” context? Would you be able to write an example to demonstrate how they differ?

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