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< h4 > Description< / h4 >
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retract(Clause)
retract((Head:-Body))
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Retracts a dynamic clause from an object.
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< h4 > Template and modes< / h4 >
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retract(+clause)
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< h4 > Errors< / h4 >
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< dt > Head is a variable:< / dt >
< dd > < code > instantiation_error< / code > < / dd >
< dt > Head is neither a variable nor a callable term:< / dt >
< dd > < code > type_error(callable, Head)< / code > < / dd >
< dt > The predicate indicator of Head is that of a private predicate:< / dt >
< dd > < code > permission_error(modify, private_predicate, Head)< / code > < / dd >
< dt > The predicate indicator of Head is that of a protected predicate:< / dt >
< dd > < code > permission_error(modify, protected_predicate, Head)< / code > < / dd >
< dt > The predicate indicator of Head is that of a static predicate:< / dt >
< dd > < code > permission_error(modify, static_predicate, Head)< / code > < / dd >
< dt > The predicate indicator of Head is not declared:< / dt >
< dd > < code > existence_error(predicate_declaration, Head)< / code > < / dd >
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< h4 > Examples< / h4 >
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< dt > To retract a matching clause of any dynamic predicate in < a class = "glossary" title = "Go to glossary definition" href = "../../glossary.html#this" > this< / a > :< / dt >
< dd > < code > retract(Clause)< / code > < / dd >
< dt > To retract a matching clause of a public or protected dynamic predicate in < a class = "glossary" title = "Go to glossary definition" href = "../../glossary.html#self" > self< / a > :< / dt >
< dd > < code > ::retract(Clause)< / code > < / dd >
< dt > To retract a matching clause of a public dynamic predicate in an object:< / dt >
< dd > < code > Object::retract(Clause)< / code > < / dd >
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< strong > < a href = "clause2.html" > Previous< / a > | < a href = "retractall1.html" > Next< / a > | < a href = "../index.html" > Table of Contents< / a > | < a href = "../../bibliography.html" > Bibliography< / a > | < a href = "../../glossary.html" > Glossary< / a > < / strong >
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2002-04-03 14:26:59 +01:00
Last updated on: April 2, 2002
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