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digitalmars.D.learn - ctRegex - named submatch

reply "Daniel" <wyrlon gmx.net> writes:
Hi,

I tried using named submatch for ctRegex... it works but 
seemingly only for maximum 1 named submatch...

OK (\w changed to \S to avoid, out of memory)
`(?P<var>\S+)\s*=\s*(\d+);`
`(?\S+)\s*=\s*(?P<value>\d+);`

NOT OK
`(?P<var>\w+)\s*=\s*(?P<value>\d+);`

Is this a known bug? I used the regex example from the Library 
Reference, converting it to ctRegex...

Lookup named submatch.
import std.regex;
import std.range;

auto m = match("a = 42;", 
regex(`(?P<var>\w+)\s*=\s*(?P<value>\d+);`));
auto c = m.captures;
assert(c["var"] == "a");
assert(c["value"] == "42");
popFrontN(c, 2);
//named groups are unaffected by range primitives
assert(c["var"] =="a");
assert(c.front == "42");
Aug 07 2012
parent reply Dmitry Olshansky <dmitry.olsh gmail.com> writes:
On 08-Aug-12 00:24, Daniel wrote:

 Hi,

 I tried using named submatch for ctRegex... it works but seemingly only
 for maximum 1 named submatch...


Great! I never tried ;) Should just work though...


 OK (\w changed to \S to avoid, out of memory)
 `(?P<var>\S+)\s*=\s*(\d+);`
 `(?\S+)\s*=\s*(?P<value>\d+);`

 NOT OK
 `(?P<var>\w+)\s*=\s*(?P<value>\d+);`


Would be great to know what exactly is not OK :) Error message etc.



 Is this a known bug? I used the regex example from the Library
 Reference, converting it to ctRegex...


I know it's hitting assert failure during parse. It's a CTFE bug, there 
are some other limitations but they are not in bugzilla yet.

That all being said experimental tag on ctRegex in DDoc is here for a 
reason, and that is: ctRegex can't compile nor match full regex testsuite.
(out of memory + bugs)

 Lookup named submatch.
 import std.regex;
 import std.range;

 auto m = match("a = 42;", regex(`(?P<var>\w+)\s*=\s*(?P<value>\d+);`));
 auto c = m.captures;
 assert(c["var"] == "a");
 assert(c["value"] == "42");
 popFrontN(c, 2);
 //named groups are unaffected by range primitives
 assert(c["var"] =="a");
 assert(c.front == "42");



-- 
Dmitry Olshansky
Aug 07 2012
parent reply "Daniel" <wyrlon gmx.net> writes:
On Tuesday, 7 August 2012 at 20:51:28 UTC, Dmitry Olshansky wrote:

 Great! I never tried ;) Should just work though...


hehe :)


 That all being said experimental tag on ctRegex in DDoc is here 
 for a reason, and that is: ctRegex can't compile nor match full 
 regex testsuite.


Understood, thanks for your quick response nevertheless. :)

There are different errors depending on which of the two captures 
is attempted to be accessed.

auto m = match("a = 42;", 
ctRegex!(`(?P<var>\S+)\s*=\s*(?P<value>\d+);`));
auto c = m.captures;

// c["var"]; =>
core.exception.RangeError std.regex(2145): Range violation

// c["value"]; =>
Object.Exception C:\D\dmd2\windows\bin\..\..\src\phobos\std\regex.d(2145): 
no su
bmatch named value
Aug 07 2012
parent Dmitry Olshansky <dmitry.olsh gmail.com> writes:
On 08-Aug-12 02:05, Daniel wrote:

 On Tuesday, 7 August 2012 at 20:51:28 UTC, Dmitry Olshansky wrote:

 That all being said experimental tag on ctRegex in DDoc is here for a
 reason, and that is: ctRegex can't compile nor match full regex
 testsuite.


 Understood, thanks for your quick response nevertheless. :)

 There are different errors depending on which of the two captures is
 attempted to be accessed.

 auto m = match("a = 42;", ctRegex!(`(?P<var>\S+)\s*=\s*(?P<value>\d+);`));
 auto c = m.captures;

 // c["var"]; =>
 core.exception.RangeError std.regex(2145): Range violation

 // c["value"]; =>
 Object.Exception C:\D\dmd2\windows\bin\..\..\src\phobos\std\regex.d(2145):
 no su
 bmatch named value


Yikes! Something is wrong with hash-table that maps names to indexes 
(it's just it).

File this as bug please, including the example.

-- 
Dmitry Olshansky
Aug 08 2012