category

# observer

> Smalltalk dependent protocol.

author:
  `Paulo Moura`
version:
  `1.0`
date:
  `2003/2/9`

compilation flags:
  `static`

(no dependencies on other entities)

## Public interface

### update/1

> Called when an observed object is updated.

compilation flags:
  `static`
template:
  `update(Change)`
mode – number of proofs:
  `update(?nonvar) – zero_or_one`

## Protected interface

(none)

## Private predicates

(none)

## Operators

### (none)

## Remarks

### (none)

## See also

- subject