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Variables in perl

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# 1  
Old 09-03-2012
Variables in perl
I don't fully understand variables in perl.

If we have a variable defined like this "my $number = 1" then this is called a lexical variable? But if you define this at the top of a script then why isn't it a global variable because it would be available throughout the file?

Sorry if this is a really stupid question to ask but I'm getting myself confused.
# 2  
Old 09-04-2012
Lexical and global refer to where the variables are stored. Global variables(symbols are another name for them) are stored in a symbol table which is maintained in memory accesible by all of the code, including a lot of packages you cannot see. Lexical variables are not in any table. Lexical variables can only refer to a scalar, an array, or a hash. Global variables can reference other things like external procedures.

Just because you write a program with "my $var" near the top does not promote the variable to being stored in a symbol table.

Perl is not C, although knowing C makes learning perl a lot easier.
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