User Tools


Differences

This shows you the differences between two versions of the page.

Link to this comparison view

cl:variables:star-default-pathname-defaults-star [2017/05/01 21:00] (current)
Line 1: Line 1:
 +====== Variable *DEFAULT-PATHNAME-DEFAULTS* ======
 +
 +====Value Type====
 +a //​[[CL:​Glossary:​pathname]]//​ //​[[CL:​Glossary:​object]]//​.
 +
 +====Initial Value====
 +An //​[[CL:​Glossary:​implementation-dependent]]//​ //​[[CL:​Glossary:​pathname]]//,​ typically in the working directory that was current when Common Lisp was started up.
 +
 +====Description====
 +a //​[[CL:​Glossary:​pathname]]//,​ used as the default whenever a //​[[CL:​Glossary:​function]]//​ needs a default //​[[CL:​Glossary:​pathname]]//​ and one is not supplied.
 +
 +====Examples==== ​
 +This example illustrates a possible usage for a hypothetical Lisp running on a DEC TOPS-20 //​[[CL:​Glossary:​file system]]//. Since //​[[CL:​Glossary:​pathname]]//​ conventions vary between Lisp //​[[CL:​Glossary:​implementation|implementations]]//​ and host //​[[CL:​Glossary:​file system]]// types, it is not possible to provide a general-purpose,​ //​[[CL:​Glossary:​conforming]]//​ example.
 +
 +<​blockquote> ​
 +*default-pathname-defaults* <​r>#​P"​PS:<​FRED>"​ </r>
 +([[CL:​Functions:​merge-pathnames]] ([[CL:​Functions:​make-pathname]] :name "​CALENDAR"​)) <​r>#​P"​PS:<​FRED>​CALENDAR"​ </r>
 +([[CL:​Special Operators:​let]] ((*default-pathname-defaults* ([[CL:​Functions:​pathname]] "<​MARY>"​))) ​
 +  ([[CL:​Functions:​merge-pathnames]] ([[CL:​Functions:​make-pathname]] :name "​CALENDAR"​))) <​r>#​P"<​MARY>​CALENDAR"</​r>​
 +</​blockquote>​
 +
 +====Affected By====
 +The //​[[CL:​Glossary:​implementation]]//​.
 +
 +====See Also====
 +None.
 +
 +====Notes====
 +None.