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Re: Patterns: Why are anchors not character classes?

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It was thus said that the Great Roberto Ierusalimschy once stated:
> > But! There is this:
> > 
> > 	%x: (where x is any non-alphanumeric character) represents the
> > 	character x. This is the standard way to escape the magic
> > 	characters. Any non-alphanumeric character (including all
> > 	punctuations, even the non-magical) can be preceded by a '%' when
> > 	used to represent itself in a pattern.
> > 
> > So to me, that says that '%%' is NOT a class and can therefore be used as
> > mentioned. I wonder what Roberto meant by the example of "[a-%%]". Perhaps
> > a typo?
> 
> Where does it say it is not a class? Read the whole story:
> 
> | The following combinations are allowed in describing a character class:
> |
> | %x: (where x is any non-alphanumeric character) represents the [...]
> 
> It is a class: a unit set, which includes only that character.
 Okay, but what were you trying to get across with "[a-%%]"? That
reverse ranges don't work? [1]
 I think I was confused because 
	
	("a"):match "[%%-a]"
worked, but in playing with it further, it seems that this created a class
of three characters, '%', '-' and 'a'. Wierd.
 -spc (Which is why I tend to use LPeg---these type of issues just go away ... )
[1]	"[z-a]" will fail, for instance.

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