Experimental Physics and
Industrial Control System

Benjamin Franksen <[email protected]> · Fri, 20 Aug 1999 17:26:21 +0200

Whoever controls epics/base/src/dbtools (Marty?)

I am frequently irritated by the error message 'Substitution file parse
error' that dbLoadTemplate issues when it encounters an empty
substitution body for an existing file, like 

file xxx.template {
}

What dbLoadTemplate does is ok (ie no instances are created), but the
message causes confusion because the user doesn't know if there is a
_real_ error, so in principle it may not be ignored safely.

I think this construct should be allowed by the parser, since
substitution files are often (at least at BESSY) generated by scripts
and the case 'no instances of this template' appears quite often.
Changing the scripts so that they do not produce the 'file xxx.template
{}' in this special case would complicate them beyond reason.

The necessary changes are simple: Allow the non-terminal symbol 'subst'
to be empty: in dbLoadTemplate.y change

subst: PATTERN pattern subs
	| var_subs
	;

to

subst: PATTERN pattern subs
	| PATTERN pattern
	| var_subs
	|
	;

I tested this and didn't notice any undesired side-effects.

Ben
-- 
The Notorious Neb Nesknarf
---------------------------------------------------------------------
@BESSY II: fax: +49 30 6392-4859 phone: +49 30 6392-4865
---------------------------------------------------------------------
keep the listeners busy: Kosovo Iran Kurdistan Albanien Libyen Heroin
Waffenlieferung FARC ELN PKK ...

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System