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cl:functions:boundp [2019/09/14 05:00]
cl:functions:boundp [2019/09/20 16:00] (current)
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 +====== Function BOUNDP ======
 +
 +====Syntax====
 +  * **boundp** //symbol// → //​generalized-boolean//​
 +
 +====Arguments and Values====
 +  * //symbol// - a //​[[CL:​Glossary:​symbol]]//​.
 +  * //​generalized-boolean//​ - a //​[[CL:​Glossary:​generalized boolean]]//​.
 +
 +====Description====
 +Returns //​[[CL:​Glossary:​true]]//​ if //symbol// is //​[[CL:​Glossary:​bound]]//;​ otherwise, returns //​[[CL:​Glossary:​false]]//​.
 +
 +====E*x*amples====
 +<​blockquote>​
 +;;; TODO condemn toplevel SETQ
 +([[CL:​Macros:​setq]] *x* 1) <​r>​1</​r>​
 +(boundp '*x*) <​r>//​[[CL:​Glossary:​true]]//​ </r>
 +([[CL:​Functions:​makunbound]] '*x*) <​r>​*X* </r>
 +(boundp '*x*) <​r>//​[[CL:​Glossary:​false]]//​ </r>
 +([[CL:​Special Operators:​let]] ((*x* 2)) 
 +  (boundp '*x*)) <​r>//​[[CL:​Glossary:​false]]//​ </r>
 +([[CL:​Special Operators:​let]] ((*x* 2)) 
 +  ([[CL:​Symbols:​declare]] ([[CL:​Declarations:​special]] *x*)) 
 +  (boundp '*x*)) <​r>//​[[CL:​Glossary:​true]]//</​r>​
 +</​blockquote>​
 +
 +====Affected By====
 +None.
 +
 +====Exceptional Situations====
 +Should signal an error of type type-error if //symbol// is not a //​[[CL:​Glossary:​symbol]]//​.
 +
 +====See Also====
 +  * **[[CL:​Functions:​set|Function SET]]**
 +  * **[[CL:​Special Operators:​setq|Special Operator SETQ]]**
 +  * **[[CL:​Functions:​symbol-value|Function SYMBOL-VALUE]]**
 +  * **[[CL:​Functions:​makunbound|Function MAKUNBOUND]]**
 +
 +====Notes====
 +The //​[[CL:​Glossary:​function]]//​ **[[CL:​Functions:​bound]]** determines only whether a //​[[CL:​Glossary:​symbol]]//​ has a value in the //​[[CL:​Glossary:​global environment]]//;​ any //​[[CL:​Glossary:​lexical binding|lexical bindings]]//​ are ignored.
 +