Missing table capture "{| p |}" in the "re" grammar

[mingodad]

Trying to use the re grammar shown at http://www.inf.puc-rio.br/~roberto/lpeg/re.html I found that it's missing the table capture {| p |} pattern.

For my usage example see here edubart/nelua-lang#190 (comment)

[edubart]

Hey @mingodad from what I've seen and used, table captures in re is there documented and working as expected, so I don't see any issues here. Also this repository is a mirror, and I don't think Roberto answers here, if you want an answer back you should ask questions or report issues in Lua mailing list, there more people will also be able to test and help.

Also make sure to be test this in pure LPeg library before reporting as LPeg issue (no LPegLabel or LPegRex forks).

[mingodad]

I'm not saying that it's not implemented, I'm saying that it's not in the documentation grammar of re, see it ammended reproduced here :

p = [=[

pattern         <- exp !.
exp             <- S (grammar / alternative)

alternative     <- seq ('/' S seq)*
seq             <- prefix*
prefix          <- '&' S prefix / '!' S prefix / suffix
suffix          <- primary S (([+*?]
                            / '^' [+-]? num
                            / '->' S (string / '{}' / name)
                            / '=>' S name) S)*

primary         <- '(' exp ')' / string / class / defined
                 / '{:' (name ':')? exp ':}'
                 / '=' name
                 / '{}'
                 / '{~' exp '~}'
                 / '{|' exp '|}'   --!!! <<< missing table capture
                 / '{' exp '}'
                 / '.'
                 / name S !arrow
                 / '<' name '>'          -- old-style non terminals

grammar         <- definition+
definition      <- name S arrow exp

class           <- '[' '^'? item (!']' item)* ']'
item            <- defined / range / .
range           <- . '-' [^]]

S               <- (%s / '--' [^%nl]*)*   -- spaces and comments
name            <- [A-Za-z][A-Za-z0-9_]*
arrow           <- '<-'
num             <- [0-9]+
string          <- '"' [^"]* '"' / "'" [^']* "'"
defined         <- '%' name

]=]

print(re.match(p, p))   -- a self description must match itself

[edubart]

Oh now I understand, indeed it is missing there. It an issue only in an example of the re documentation page then.

Still chances are higher of that being fixed if this gets reported in the Lua mailing list.

[mingodad]

The mentioned grammar also is missing an underscore for the first character of a name that is in code and is accepted:
In the documentation:

name            <- [A-Za-z][A-Za-z0-9_]*

In the code:

name            <- [A-Za-z_][A-Za-z0-9_]*