GNU Info

(slib.info)Rev2 Procedures

---

Next: Rev4 Optional Procedures Prev: Transcripts Up: Standards Support

---

Enter node , (file) or (file)node

Rev2 Procedures
---------------

  `(require 'rev2-procedures)'

  The procedures below were specified in the `Revised^2 Report on
Scheme'.  *N.B.*: The symbols `1+' and `-1+' are not `R4RS' syntax.
Scheme->C, for instance, barfs on this module.

 - Procedure: substring-move-left! string1 start1 end1 string2 start2
 - Procedure: substring-move-right! string1 start1 end1 string2 start2
     STRING1 and STRING2 must be a strings, and START1, START2 and END1
     must be exact integers satisfying

          0 <= START1 <= END1 <= (string-length STRING1)
          0 <= START2 <= END1 - START1 + START2 <= (string-length STRING2)

     `substring-move-left!' and `substring-move-right!' store
     characters of STRING1 beginning with index START1 (inclusive) and
     ending with index END1 (exclusive) into STRING2 beginning with
     index START2 (inclusive).

     `substring-move-left!' stores characters in time order of
     increasing indices.  `substring-move-right!' stores characters in
     time order of increasing indeces.

 - Procedure: substring-fill! string start end char
     Fills the elements START-END of STRING with the character CHAR.

 - Function: string-null? str
     == `(= 0 (string-length STR))'

 - Procedure: append! pair1 ...
     Destructively appends its arguments.  Equivalent to `nconc'.

 - Function: 1+ n
     Adds 1 to N.

 - Function: -1+ n
     Subtracts 1 from N.

 - Function: <?
 - Function: <=?
 - Function: =?
 - Function: >?
 - Function: >=?
     These are equivalent to the procedures of the same name but
     without the trailing `?'.