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====== Function DESCRIBE ====== ====Syntax==== * **describe** //object ''&optional'' stream// → //<no values>// ====Arguments and Values==== * //object// - an //[[CL:Glossary:object]]//. * //stream// - an //[[CL:Glossary:output]]// //[[CL:Glossary:stream designator]]//. The default is //[[CL:Glossary:standard output]]//. ====Description==== **describe** displays information about //object// to //stream//. For example, **describe** of a //[[CL:Glossary:symbol]]// might show the //[[CL:Glossary:symbol]]//'s value, its definition, and each of its properties. **describe** of a //[[CL:Glossary:float]]// might show the number's internal representation in a way that is useful for tracking down round-off errors. In all cases, however, the nature and format of the output of **describe** is //[[CL:Glossary:implementation-dependent]]//. **describe** can describe something that it finds inside the //object//; in such cases, a notational device such as increased indentation or positioning in a table is typically used in order to visually distinguish such recursive descriptions from descriptions of the argument //object//. The actual act of describing the object is implemented by **[[CL:Functions:describe-object]]**. **describe** exists as an interface primarily to manage argument defaulting (including conversion of arguments **[[CL:Constant Variables:t]]** and **[[CL:Constant Variables:nil]]** into //[[CL:Glossary:stream]]// //[[CL:Glossary:object|objects]]//) and to inhibit any return values from **[[CL:Functions:describe-object]]**. **describe** is not intended to be an interactive function. In a //[[CL:Glossary:conforming implementation]]//, **describe** must not, by default, prompt for user input. User-defined methods for **[[CL:Functions:describe-object]]** are likewise restricted. ====Examples==== None. ====Side Effects==== Output to //[[CL:Glossary:standard output]]// or //[[CL:Glossary:terminal I/O]]//. ====Affected By==== **[[CL:Variables:star-standard-output-star|*standard-output*]]** and **[[CL:Variables:star-terminal-io-star|*terminal-io*]]**, methods on **[[CL:Functions:describe-object]]** and **[[CL:Functions:print-object]]** for //[[CL:Glossary:object|objects]]// having user-defined //[[CL:Glossary:classes]]//. ====Exceptional Situations==== None. ====See Also==== **[[CL:Functions:inspect|Function INSPECT]]**, **[[CL:Functions:describe-object|Function DESCRIBE-OBJECT]]** ====Notes==== None. \issue{DESCRIBE-UNDERSPECIFIED:DESCRIBE-OBJECT} \issue{DESCRIBE-UNDERSPECIFIED:DESCRIBE-OBJECT} \issue{DESCRIBE-UNDERSPECIFIED:DESCRIBE-OBJECT} \issue{DESCRIBE-INTERACTIVE:NO}