This is a special analog of cl:string. A pure-string is a string stored in a .pll file. These strings can be shared (among different simultaneous invocations of Lisp), but they are constants and cannot be modified. This function takes x (which must be a string or a symbol) and searches pure space to see if the string (printname if x is a symbol) is already there. If it is, that string is returned. If it is not, a new string is allocated in the heap and returned. So, if you know a string is a constant, you can apply this function to it to get the associated pure string if there is one, and thus save space.
When building a .str file using record-strings, pure-string will record that string that will be returned into the .str file for later processing by cvdcvt, the program that creates pll files. See Creating and using pll files in miscellaneous.htm for information on pll files and cvdcvt.
As with string, x can be either a string or a symbol. If it is a string, it or its pure equivalent is returned. If it is a symbol, the printname is returned, again as a pure string if possible.
The documentation is described in introduction.htm and the index is in index.htm.
Copyright (c) 1998-2000, Franz Inc. Berkeley, CA., USA. All rights reserved.