Predicate property

From Prologstandard

Contents 1 built-in 1.1 Existing standard 1.2 In progress 2 extended/foreign 3 standard/standard(Version) 4 listable 5 definition_available/source_available

built-in

Existing standard

8 Built-in predicates:

• A built-in predicate is a procedure which is provided automatically by a *standard-conforming processor, (page 63).

5.5.9 Built-in predicates:

• A processor may support one or more additional built-in predicates (8) as an implementation specific feature.

7.5 (Database):

• Built-in predicates and control constructs are provided by the processor. They have properties which are defined by the clauses in this part of ISO/IEC 13211.

In progress

Options:

• standardise
• don't standardise

Meanings:

• cannot be abolished

extended/foreign

A new predicate property to identify code written in an external language:

Options:

• predicate properties only for the core standard
• predicate properties related to extensions outside the core standard

Naming:

• extended
• foreign
• both

standard/standard(Version)

built-ins defined by the standard of version

Options:

• add to standard
• don't add to standard

listable

clause/2 can access the predicate.

definition_available/source_available

clause/[2,3] can be called on this predicate

Options:

• add to standard
• don't add to standard

Naming:

• definition_available
• source_available

There are several clearly distinct properties: