protocol

# monitoring

> Event handlers protocol. The handlers are automatically called for messages sent using the ::/2 control construct from within objects compiled with the "events" flag set to "allow".

author:
  `Paulo Moura`
version:
  `1.0`
date:
  `2013/5/4`

compilation flags:
  `static, built_in`

(no dependencies on other files)

## Public interface

### before/3

> Event handler for "before" events. A "before" event handler may prevent a method from being looked up or called by failing.

compilation flags:
  `static`
template:
  `before(Object,Message,Sender)`
mode – number of proofs:
  `before(@term,@term,@term) – zero_or_one`

### after/3

> Event handler for "after" events. An "after" event handler may prevent a method from succeeding by failing.

compilation flags:
  `static`
template:
  `after(Object,Message,Sender)`
mode – number of proofs:
  `after(@term,@term,@term) – zero_or_one`

## Protected interface

(none)

## Private predicates

(none)

## Operators

### (none)

## Remarks

### (none)

## See also

### (none)