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# caller

Perl 5 version 10.1 documentation
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# caller

Perl functions A-Z | Perl functions by category | The 'perlfunc' manpage

- caller EXPR

- caller

  Returns the context of the current subroutine call. In scalar context, returns the caller's package name if there is a caller, that is, if we're in a subroutine or `eval` or `require`, and the undefined value otherwise. In list context, returns

          # 0         1          2    ($package, $filename, $line) = caller;

  With EXPR, it returns some extra information that the debugger uses to print a stack trace. The value of EXPR indicates how many call frames to go back before the current one.

          #  0         1          2      3            4    ($package, $filename, $line, $subroutine, $hasargs,    #  5          6          7            8       9         10    $wantarray, $evaltext, $is_require, $hints, $bitmask, $hinthash)     = caller($i);

  Here $subroutine may be `(eval)` if the frame is not a subroutine call, but an `eval`. In such a case additional elements $evaltext and `$is_require` are set: `$is_require` is true if the frame is created by a `require` or `use` statement, $evaltext contains the text of the `eval EXPR` statement. In particular, for an `eval BLOCK` statement, $subroutine is `(eval)` , but $evaltext is undefined. (Note also that each `use` statement creates a `require` frame inside an `eval EXPR` frame.) $subroutine may also be `(unknown)` if this particular subroutine happens to have been deleted from the symbol table. `$hasargs` is true if a new instance of `@_` was set up for the frame. `$hints` and `$bitmask` contain pragmatic hints that the caller was compiled with. The `$hints` and `$bitmask` values are subject to change between versions of Perl, and are not meant for external use.

  `$hinthash` is a reference to a hash containing the value of `%^H` when the caller was compiled, or `undef` if `%^H` was empty. Do not modify the values of this hash, as they are the actual values stored in the optree.

  Furthermore, when called from within the DB package, caller returns more detailed information: it sets the list variable `@DB::args` to be the arguments with which the subroutine was invoked.

  Be aware that the optimizer might have optimized call frames away before `caller` had a chance to get the information. That means that `caller(N)` might not return information about the call frame you expect it do, for `N > 1` . In particular, `@DB::args` might have information from the previous time `caller` was called.

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