---
name: "Kavorka::Manual::MethodModifiers"
section: "3pm"
platform: "linux"
package: "libkavorka-perl"
version: "0.039-3"
release: "Debian 10 (Buster)"
platforms: ["linux"]
url: "https://new.carta.tech/Kavorka::Manual::MethodModifiers"
---

# Kavorka::Manual::MethodModifiers(3pm)

before/after/around keywords

## NAME

Kavorka::Manual::MethodModifiers - before/after/around keywords

## DESCRIPTION

Kavorka provides the `"before"`, `"after"` and `"around"` keywords for method modifiers.

Method modifiers should work in Moose, Moo, Mouse and Role::Tiny classes and roles. In other classes they will fall back to using Class::Method::Modifiers.

The keywords `"augment"` and `"override"` are also available, but will only work in classes backed by a framework that supports these modifiers (i.e. Moose or Mouse, but *not* Moo).

The anatomy of a method modifier:

- 1\.

  The keyword introducing the method.

- 2\.

  The method names.

- 3\.

  The signature (optional).

- 4\.

  Traits (optional).

- 5\.

  The prototype (optional).

- 6\.

  The attribute list (optional).

- 7\.

  The modifier body.

Example:

```
   #  (1)   (2)    (3)    (4)     (5)  (6)     (7)
      after foobar ($foo) is cool :($) :cached { $self->log("foobar $foo") }
```

### The Keyword

By default, these keywords are exported. They must be exported by request:

```
   use Kavorka qw( before after around );
   use Kavorka qw( -modifiers );
```

### The Method Names

These are the names of the methods being wrapped.

Multiple names may be separated by colons:

```
   after foo, bar, baz { ... }
```

### The Signature

See Kavorka::Manual::Signatures.

The `"before"` and `"after"` keywords have a default invocant called `$self`, but it does not have a type constraint, so can equally be used for class or object methods.

The `"around"` modifier defines two invocants called `$next` and `$self`. (`"${^NEXT}"` is also available as an alias for `$next` for backwards compatibility with Moops::MethodModifiers.)

Beware using type constraints for method modifiers (which are essentially wrappers); constraints will be checked at each level of wrapping which will slow down method calls.

### Traits

See Kavorka::Manual::ExtendingKavorka.

### The Prototype

See Kavorka::Manual::PrototypeAndAttributes.

Note however that prototypes are fairly useless for methods.

### The Attributes

Attributes may alternatively be provided *before the signature*.

See Kavorka::Manual::PrototypeAndAttributes.

Note that this applies the attribute to the modifier code, and not to the method being modified.

### The Modifier Body

This is more or less what you'd expect from the modifier body you'd write with Moose, however the lexical variables for parameters are pre-declared and pre-populated, and invocants have been shifted off `@_`.

## BUGS

Please report any bugs to \<http://rt.cpan.org/Dist/Display.html?Queue=Kavorka\>.

## SEE ALSO

Kavorka::Manual, Kavorka::Manual::Signatures, Kavorka::Manual::PrototypeAndAttributes, Kavorka::Manual::Methods.

## AUTHOR

Toby Inkster \<tobyink@cpan.org\>.

## COPYRIGHT AND LICENCE

This software is copyright (c) 2013-2014, 2017 by Toby Inkster.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

## DISCLAIMER OF WARRANTIES

THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.