perl subroutine help

In the iw_solution_email.ipl, I found some subroutine has a number of $ sign.
e.g.
sub Generate_Part($$)
sub Send_Email($$$$$)

I am a new perl programmer. And would like to know what is the $ sign mean. Thanks!

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Pawan

In the iw_solution_email.ipl, I found some subroutine has a number of $ sign.
e.g.
sub Generate_Part($$)
sub Send_Email($$$$$)

I am a new perl programmer. And would like to know what is the $ sign mean. Thanks!

These are the number of arguments you are fetching when calling the function Send_Email - 5 arguments.
You can even skip this by defining sub Send_Email without any $ sign.

kaalraa

Apart from what Pawan has said, if you are using $ then you must have to pass that much number of parameters to that particular function... it can be an undefined value as well.

Adam Stoller

In the iw_solution_email.ipl, I found some subroutine has a number of $ sign.
e.g.
sub Generate_Part($$)
sub Send_Email($$$$$)

I am a new perl programmer. And would like to know what is the $ sign mean. Thanks!

These are called prototypes in which one defines the number and types of parameters that the subroutine expects to be called with. However, and I quote:

Prototypes cause far more trouble than they avert. Even when they are properly understood and used correctly, they create code that doesn't behave the way it looks like it ought to, which makes it harder to maintain code that uses them. Furthermore, in OO implementations then engender a completely false sense of security, because they're utterly ignored in any method call.

Don't use proptotypes. ...

In the above examples you show, it indicated that Generate_Part expects two scalar parameters, and Send_Email expects five scalar parameters.