[stringtemplate-interest] no "..." pass through argument for v4?

[Terence Parr]

It meant don't let arg x hide an x in enclosing scope.  in effect same thing.
Ter
On Jan 12, 2011, at 11:50 AM, Sam Harwell wrote:

> I thought the '...' meant assign all remaining parameters by name to the
> arguments in the current scope. For example, for the following definition of
> ruleA, each definition of ruleB performs exactly the same.
> 
> ruleA(x,y,z) ::= ""
> 
> ruleB(x,y,z) ::= "ruleA(x=x,y=y,z=z)"
> ruleB(x,y,z) ::= "ruleA(x=x,...)"
> ruleB(x,y,z) ::= "ruleA(...)"
> 
> If that's really the case, then the '...' shouldn't be a performance
> problem. Perhaps I'm missing something about the behavior of the '...'?
> 
> Sam
> 
> -----Original Message-----
> From: stringtemplate-interest-bounces at antlr.org
> [mailto:stringtemplate-interest-bounces at antlr.org] On Behalf Of Terence Parr
> Sent: Wednesday, December 22, 2010 2:26 PM
> To: stringtemplate-interest at antlr.org List
> Subject: [stringtemplate-interest] no "..." pass through argument for v4?
> 
> In v3 we have a ... arg that lets us see dynamically inherited values
> through arguments like this:
> 
> /** i+=INT in lexer */
> lexerRuleRefAndListLabel(rule,label,args,elementIndex,scope) ::= <<
> <lexerRuleRef(...)> <listLabel(elem=label,...)>
>>> 
> 
> it's just bein lazy, not passing arguments along.  It has a big peformance
> hit so i think i'll drop for v4.  
> 
> Consider
> 
> f(a) ::= "<name>_<a>"
> 
> arg 'a' is clearly immediately available w/o looking up the chain of
> enclosing templates so it should be a fast array lookup.  name is clearly
> not defined as arg and so slower lookup is needed.  If we allow "<f(...)>"
> the assumption that 'a' is an arg is no longer true.
> 
> Ter
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