On 2013-12-21, at 05:51, John Gilmore wrote:

> EJ's macro can of course be written in the form
>
>          MACRO ,
> &LABEL  DIAG  &R1,&R2,&I1
> &LABEL  LA    &R1,&I1.(&R2.,0)    Diagnose
>          ORG   &LABEL
>          DC    X'83'
>          ORG  ,
>          MEXIT  ,
>          MEND  ,
>
> and this form, which delegates the location-counter arithmetic to the
> assembler, seems to me to be at once clearer and less error-prone.
>
Agreed.

> Dijkstra's epigoni have conditioned many people to avoid the use of
> labels whenever possible, even at the expense of real ugliness, not
> present here; but the use of an already present label in this way
> seems to me to be entirely benign.   Moreover, their judicious use
> often makes it possible to avoid what Tony Harminc has just called
> "fancier ORGs".
>
Agreed.  But the ORG without argument may not do what you desire:
It sets the location counter to the previous highwater mark, which
may, because of prior ORGs, be elsewhere than the end of the LA.

-- gil

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