From: Steve Wright [usenet@wrightnet.demon.co.uk]
Sent: Wednesday, January 30, 2002 6:21 PM
To: Info-VAX@Mvb.Saic.Com
Subject: Re: STR$lowercase ?

In message <slrna5bs8l.ngh.danco@pebble.org>, danco@pebble.org writes
>In article <3C55B3D5.5F431CAB@UIowa.EDU>, Rick Dyson wrote:
>
>>>     In the past I've used calls to BAS$EDIT, IIRC.  There was an old
>
>
>Umm, but BAS$EDIT doesn't have "uppercase to lowercase" functionality,
>does it?  I don't see it in any case.  :-)
>
>
>EDIT$
>
>  Syntax
>
>
>           str-var = EDIT$(str-exp, int-exp)
>
>               Values   Effect
>
>               1%       Trim parity bits
>               2%       Discard all spaces and tabs
>               4%       Discard characters: CR, LF,FF, ESC, RUBOUT, and NULL
>               8%       Discard leading spaces and tabs
>               16%      Reduce spaces and tabs to one space
>               32%      Convert lowercase to uppercase
>               64%      Convert [ to ( and ] to )
>               128%     Discard trailing spaces and tabs
>               256%     Do not alter characters inside quotes
>
>- Dan

I don't know the name of the library routine, but when we wanted to do 
something similar in DEC-BASIC, we used the XLATE function.

 From the on-line VMS manual

================== START OF CUT & PASTE ===============================

XLATE$

The XLATE$ function translates one string to another by referencing a 
table string you supply.

-----------------------------------------------------------------------

Format

Str-result = xlate (Str-exp1, Str-exp2)
------------------------------------------------------------------------

-----------------------------------------------------------------------

Syntax Rules
Str-exp1 is the input string.
Str-exp2 is the table string.

-----------------------------------------------------------------------

Remarks
Str-exp2 can contain up to 256 ASCII characters, numbered from 0 to 255; 
the position of each character in the string corresponds to an ASCII 
value. Because 0 is a valid ASCII value (null), the first position in 
the table string is position zero.
XLATE$ scans str-exp1 character by character, from left to right. It 
finds the ASCII value n of the first character in str-exp1 and extracts 
the character it finds at position n in str-exp2. XLATE$ then appends 
the character from str-exp2 to str-var. XLATE$ continues this process, 
character by character, until the end of str-exp1 is reached.
The output string may be smaller than the input string for the following 
reasons:
XLATE$ does not translate nulls. If the character at position n in 
str-exp2 is a null, XLATE$ does not append that character to str-var.
If the ASCII value of the input character is outside the range of 
positions in str-exp2, XLATE$ does not append any character to str-var.


------------------------------------------------------------------------

Example


DECLARE STRING A, table, source
A = "abcdefghijklmnopqrstuvwxyz"
table = STRING$(65, 0) + A
LINPUT " Type a string of uppercase letters"; source
PRINT XLATE$(source, table)




Output



Type a string of uppercase letters? ABCDEFG
abcdefg

================== END OF CUT & PASTE ==================================


Well look at that... the example in the manual shows how to convert 
uppercase to lowercase, although it does strip any non uppercase 
characters :-(

Better to do something like

TABLE = ""
FOR I = 0% TO ASCII ("A") - 1%
     TABLE = TABLE + CHR$ (I)
NEXT I
TABLE = TABLE + "abcdefghijklmnopqrstuvwxyz"
FOR I = ASCII ("Z") + 1% TO 255%
     TABLE = TABLE + CHR$ (I)
NEXT I

to set up the table. That way, any non uppercase characters are 
preserved.


-- 
Steve Wright