March 2005
Intermediate to advanced
1064 pages
34h 51m
English
Content preview from Pro Perl
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CHAPTER 8Scope and Visibility
We touched on the concept of scope briefly in Chapter 2 and mentioned it in following chapters from time to time without going into the full details. The scope of a variable is simply the range of places in code from which the variable can be accessed. However, there are two fundamentally different types of variable scope in Perl: package scope (also called dynamic scope) and lexical scope. Which one we use depends on how variables are declared. Named subroutines, on the other hand, always have package scope, as they are defined within a package. This is why we can call a subroutine in another package, and also why it makes no sense to define one subroutine inside another. Anonymous subroutine references are scalars, ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.