Re: Not able to use x3::skip(skipper)[some recursive rule] in its rule definition

On 07/25/2017 07:43 AM, Han Wang wrote:
> Hi Larry,
> 
> Thanks. I've tried this get_rhs branch but it doesn't solve this 
> problem. Still get the same error.
> 
> Best regards,
> Han
> 
[snip]

OPPS.  Sorry about that.  I should have read where you say in OP:

it will generate an infinite context (by x3::make_context in 
x3::skip_directive).

I just saw the x3::make_context and remembered that was causing
long compile times.  There's a make_unique_context which
avoids the infinite recursion.  When that's applied, as shown here:

https://github.com/cppljevans/spirit/blob/get_rhs/include/boost/spirit/home/x3/directive/skip.hpp#L40

Compile succeeds fast:

make compile
time 
/home/evansl/dwnlds/llvm/3.9/prebuilt/clang+llvm-3.9.0-x86_64-linux-gnu-ubuntu-16.04/bin/clang++ 
-c -O0 -stdlib=libc++  -std=c++1z -ftemplate-backtrace-limit=0 
-fdiagnostics-show-template-tree -fno-elide-type 
-fmacro-backtrace-limit=0     -c -std=c++14 -ftemplate-depth=1024 
-I/home/evansl/prog_dev/boost/releases/ro/boost_1_64_0/sandbox/pull_requests/context_debug_fix.fork/spirit/include 
-I/home/evansl/prog_dev/boost/releases/ro/boost_1_64_0 
-DBOOST_SPIRIT_GET_RHS_CRTP=0 -DBOOST_SPIRIT_ATTR_XFORM_IN_RULE=0  main.cpp
In file included from main.cpp:7:
In file included from 
/home/evansl/prog_dev/boost/releases/ro/boost_1_64_0/sandbox/pull_requests/context_debug_fix.fork/spirit/include/boost/spirit/home/x3.hpp:17:
In file included from 
/home/evansl/prog_dev/boost/releases/ro/boost_1_64_0/sandbox/pull_requests/context_debug_fix.fork/spirit/include/boost/spirit/home/x3/nonterminal.hpp:10:
/home/evansl/prog_dev/boost/releases/ro/boost_1_64_0/sandbox/pull_requests/context_debug_fix.fork/spirit/include/boost/spirit/home/x3/nonterminal/rule.hpp:18:11: 
warning:
       deprecated. May cause link error when using 
BOOST_SPIRIT_INSTANTIATE. [-W#pragma-messages]
   #pragma message "deprecated.  May cause link error when using 
BOOST_SPIRIT_INSTANTIATE."
           ^
/home/evansl/prog_dev/boost/releases/ro/boost_1_64_0/sandbox/pull_requests/context_debug_fix.fork/spirit/include/boost/spirit/home/x3/nonterminal/rule.hpp:22:11: 
warning:
       deprecated. May cause excessive compile times when many rules. 
[-W#pragma-messages]
   #pragma message "deprecated.  May cause excessive compile times when 
many rules."
           ^
2 warnings generated.

real	0m2.351s
user	0m1.372s
sys	0m0.072s

Compilation finished at Tue Jul 25 08:53:02

HTH.

-regards,
Larry




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