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A PCRE internal error occured. This might be caused by a faulty plugin

====== Function FUNCTIONP ====== ====Syntax==== * **functionp** //object// → //generalized-boolean// ====Arguments and Values==== * //object// - an //[[CL:Glossary:object]]//. * //generalized-boolean// - a //[[CL:Glossary:generalized boolean]]//. ====Description==== Returns //[[CL:Glossary:true]]// if //object// is of //[[CL:Glossary:type]]// **[[CL:Types:function]]**; otherwise, returns //[[CL:Glossary:false]]//. ====Examples==== <blockquote> (functionp '[[CL:Functions:append]]) <r>//[[CL:Glossary:false]]// </r> (functionp #'[[CL:Functions:append]]) <r>//[[CL:Glossary:true]]// </r> (functionp ([[CL:Functions:symbol-function]] '[[CL:Functions:append]])) <r>//[[CL:Glossary:true]]// </r> ([[CL:Special Operators:flet]] ((f () 1)) (functionp #'f)) <r>//[[CL:Glossary:true]]// </r> (functionp ([[CL:Functions:compile]] [[CL:Constant Variables:nil]] '([[CL:Macros:lambda]] () 259))) <r>//[[CL:Glossary:true]]// </r> (functionp [[Cl:Constant Variables:nil]]) <r>//[[CL:Glossary:false]]// </r> (functionp 12) <r>//[[CL:Glossary:false]]// </r> (functionp '([[CL:Macros:lambda]] (x) ([[CL:Functions:math-multiply|*]] x x))) <r>//[[CL:Glossary:false]]// </r> (functionp #'([[CL:Symbols:lambda]] (x) ([[CL:Functions:math-multiply|*]] x x))) <r>//[[CL:Glossary:true]]//</r> </blockquote> ====Side Effects==== None. ====Affected By==== None. ====Exceptional Situations==== None. ====See Also==== None. ====Notes==== <blockquote> (functionp //object//) ≡ (typep //object// 'function) </blockquote> \issue{FUNCTION-TYPE:X3J13-MARCH-88}