Re: historysize

[Hans-Bernhard B. <br...@ph...>]

Daniel J Sebald wrote:
> [Hans' point]
>> Now imagine somebody who just happens to have an old gnuplot script
>> that defines all of the above variables equals to 5.  Or to 1/0, for that
>> matter, or 1.0e300.

> My first question is Why are you defining "unlimited" to mean 5?  

I'm not.  But some user very well might have a perfectly valid reason 
for doing so.  He might even have decided to use it as an expression in 
some place where the current code expects a number, just because he 
could.  This would be even worse with the single-letter alternatives 
I've seen mentioned elsewhere in this thread.

 > Second question is how popular is the redefining of keywords?

It's not --- because it's impossible.  But OTOH, "unlimited" has never 
been a keyword in gnuplot before, so if you introduce it now, you always 
run the risk of colliding with existing user-defined variables or functions.

The point is that any syntax that allows either a keyword or a number in 
a given position of the command introduces a parsing ambiguity, because 
we generally allow numeric variables to be used in *every* place where a 
numeric constant could be, and such variables are essentially 
indistinguishable from keywords.

User-defined variables and functions have been in gnuplot effectively 
forever.  Which means that in case of a parsing conflict, they must take 
precedence, or we risk breaking users' scripts for no valid reasons.