POSINS()
 Inserts characters at a particular position within a string
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 Syntax

     POSINS(<cString>,<cInsertstring>,[<nPosition>])
        --> cString

 Arguments

     <cString>  Designates the character string into which characters are
     inserted.

     <cInsertstring>  Designates the new characters that are inserted
     into <cString>.

     <nPosition>  Designates the position where the new characters are
     inserted within <cString>.  The default value inserts the characters in
     front of the last character.

 Returns

     POSINS() returns the string with the inserted characters.

 Description

     You can use POSINS() to insert characters into an existing character
     string.  The <cInsertstring> characters are inserted into the <cString>
     at the location specified by <nPosition>.

 Note

     .  The resulting character string is longer than the original, so
        this function cannot be called by reference.

 Examples

     .  Insert "123" at position 2:

        ? POSINS("abcdefgh", "123", 2)   // "a123bcdefgh"

     .  Insert "123" at position 8:

        ? POSINS("abcdefgh", "123", 8)   // "abcdefg123h"

     .  Give an erroneous position:

        ? POSINS("abcdefgh", "123", 10)  // "abcdefgh"