Perl Programming/Keywords/sub
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The sub keyword
[edit | edit source]The sub keyword defines a subroutine. Without a BLOCK, it is a forward declaration. By an assignment larger or shorter than LENGTH, the string will grow or shrink respectively to accommodate it. Without NAME, it defines an anonymous function, but returns the CODE ref of the just created closure.
Syntax
[edit | edit source] sub NAME BLOCK
sub NAME (PROTO) BLOCK
sub NAME : ATTRIBUTES BLOCK
sub NAME (PROTO) : ATTRIBUTES BLOCK
Examples
[edit | edit source]sub { $x = 1; };
sub sam { ... };