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# meta_predicate_pattern(?Pattern)

Describes built-in ECLiPSe meta-predicate patterns

Pattern
  Prolog term describing the meta-predicate pattern

## Description

This predicate returns a structure, Pattern, that describes the control flow through the arguments of a meta-predicate.

The functor and arity of Pattern correspond to the functor and arity of the meta-predicate. The arguments are each populated with one of the following atomic descriptors:

    u

  A goal that is unconditionally called whenever the predicate is called.

    e

  A goal whose exit leads unconditionally to the predicate exit.

    s

  A goal whose behaviour is the combination of `u` and `e`.

    :

  A goal that is called directly.

    0

  A goal that is not directly called, but is further processed.

An integer

  A goal that is constructed by appending the number of specified arguments.

    c

  A clause.

    p

  A PredSpec.

    *

  An argument that is not one of the above.

### Fail Conditions

no

### Resatisfiable

yes

## See Also

instrument : instrument / 2, instrument : instrument / 3, library(instrument), instrument : struct(itemplate)