<RefEntry id="list-member-find"> <!-- This file is generated automatically from the DSSSL source. --> <!-- Do not edit this file! --> <?html-filename list-member-find.html> <RefMeta> <RefEntryTitle>list-member-find</RefEntryTitle> <RefMiscInfo Role="file">dblib.dsl</RefMiscInfo> </RefMeta> <RefNameDiv> <RefName>list-member-find</RefName> <RefPurpose>Returns the index of an element in a list</RefPurpose> </RefNameDiv> <RefSynopsisDiv><Title>Synopsis</Title> <Synopsis> (list-member-find element elementlist) </Synopsis> </RefSynopsisDiv> <RefSect1><Title>Description</Title> <para> Returns the index of <literal>element</literal> in the list <literal>elementlist</literal>. The first element in a list has index 0.</para> </RefSect1> <RefSect1><Title>Author</Title> <para> Norman Walsh, <ndw@nwalsh.com> </para> </RefSect1> <RefSect1><Title>Source Code</Title> <ProgramListing> (define (list-member-find element elementlist) ;; Returns the index of an element in a list (let loop ((elemlist elementlist) (count 0)) (if (null? elemlist) -1 (if (equal? element (car elemlist)) count (loop (cdr elemlist) (+ count 1)))))) </ProgramListing> </RefSect1> </RefEntry>