Article 157024 of comp.os.vms:
In article <LEVITTE.96Oct12011815@devil.bofh.se>, levitte@lp.se (Richard Levitte - VMS Whacker) writes:
> In article <c=CH%a=_%p=BDNHQ%l=BDNCS1961011120153CN005100@bdncs1.dynawell.ch> Matthias Naidu <Naidu@dynawell.ch> writes:
> 
>    I like that one:
> 
>    $ a="123"
>    $ a[2,1]=a
>    $ SHOW SYMBOL a
>      A = "12A"
> 
> How did you make that work?  Here's how well it worked for me (VMS 6.2):

He just missed the colon:

	$ a="123"
	$ a[2,1]:=a
	$ SHOW SYMBOL a
	  A = "12A"

The only trick being displayed is the little known but plainly documented
fact that one can target DCL assignments to symbol substrings.

With the plain equal sign, the [offset,size] are in units of bits and
the right hand side must be numeric.  The right hand side is subject
to automatic expression evaluation.

With the colon-equal, the [offset,size] are in units of characters and
the right hand side is taken as a character string.  The right hand side
is not subject to automatic expression evaluation.

	John Briggs			vaxs09@alpha.vitro.com