On Thu, May 21, 2020 at 08:40:08PM +0000, David Santiago wrote:
> Can someone explain me why my grammar isn't working? Unfortunately i
> can't figure it out :-(
>
> | headers
> | | header
> | | * MATCH "Proxy-Connection"
> | | header-value
> | | * MATCH "keep-alive\n"
> | | crlf
> | | * FAIL
> | * FAIL
> * FAIL
> Nil
Notice how <header-value> is capturing the newline in "keep-alive\n"? That
means there's not a newline for the <.crlf> subrule that follows, and thus the
match fails.
Try changing "rule header-value" to be a "token" instead. That will prevent it
from consuming any whitespace immediately following the <graph>+ sequence.
When I tried your script with header-value defined as a token, it got a lot
farther into the match:
$ rakudo test.raku
TOP
| request-line
| | method
| | * MATCH "CONNECT"
| | request-uri
| | * MATCH "ssl.gstatic.com:443"
| | http-version
| | * MATCH "HTTP/1.1"
| | crlf
| | * MATCH "\n"
| * MATCH "CONNECT ssl.gstatic.com:443 HTTP/1.1\n"
| headers
| | header
| | * MATCH "Proxy-Connection"
| | header-value
| | * MATCH "keep-alive"
| | crlf
| | * MATCH "\n"
| * MATCH "Proxy-Connection: keep-alive\n"
* MATCH "CONNECT ssl.gstatic.com:443 HTTP/1.1\nProxy-Connection: keep-"
Nil
Personally, I would likely define <header-value> to be something more like
token header-value { \N+ }
which gets any sequence of non-newline characters, since some of the headers
coming afterwards contain spaces and characters which aren't part of <graph>.
Pm
