Re: Lpeg grammar questions

[Simon Cozens <simon@...>]

On 12/02/2014 22:42, Duncan Cross wrote:
> Looks like a typo here...? "linenum" is just thrown away, when it
> looks like it should probably be the second parameter of Cg().

Good catch - but even with:

 local incrementline = Cg( (Cb("linenum") / function ( a ) print("NL"); 
return a + 1 end), "linenum")

The function still doesn't fire:

> texlike:match("foo \n bar")
New
{
  line = 1,
  text = [[foo
 bar]],
}

Here's an even more reduced case:

local newline = P"\r"^-1 * "\n" / function (a) print("newline"); end
local incrementline = Cg ( Cb"linenum" / function ( a ) 
print("incrementline"); return a + 1 end , "linenum" )
local setup = Cg ( Cc ( 1) , "linenum" )
local test = (setup * newline * incrementline):match("\n")
test:match("\n")

Produces:

newline

Why doesn't incrementline do anything when it matches? (Incidentally, I've 
just tried the example where I got this pattern from and it doesn't work. :( )