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digitalmars.D - DMD back end dev-kit

reply Bill Baxter <dnewsgroup billbaxter.com> writes:
It's been talked about before, but exactly how much money do the people 
who own the copyright to DMD's backend want in order to make it freely 
available freely -- as at least a lib?  It's hard to believe anyone 
would appraise that thing with a high dollar value given its less than 
stellar optimization abilities, and since everyone knows you can't make 
much money off dev tools these days anyway.

I'd happily chip in $100 US if it meant finally having an official D 
compiler that anyone can recompile for themselves just by typing "make dmd".

Or is it more a matter of not being able to find the copyright holders 
in question to ask them?  If so, give us the names and whatever info you 
have, and I bet someone will be able to track 'em down.

--bb
Jul 01 2008
next sibling parent reply John Reimer <terminal.node gmail.com> writes:
Hello Bill,

 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make it
 freely available freely -- as at least a lib?  It's hard to believe
 anyone would appraise that thing with a high dollar value given its
 less than stellar optimization abilities, and since everyone knows you
 can't make much money off dev tools these days anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing "make
 dmd".
 
 Or is it more a matter of not being able to find the copyright holders
 in question to ask them?  If so, give us the names and whatever info
 you have, and I bet someone will be able to track 'em down.
 
 --bb
 

I'd give another $100. -JJR
Jul 01 2008
parent reply Robert Fraser <fraserofthenight gmail.com> writes:
John Reimer Wrote:

 Hello Bill,
 
 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make it
 freely available freely -- as at least a lib?  It's hard to believe
 anyone would appraise that thing with a high dollar value given its
 less than stellar optimization abilities, and since everyone knows you
 can't make much money off dev tools these days anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing "make
 dmd".
 
 Or is it more a matter of not being able to find the copyright holders
 in question to ask them?  If so, give us the names and whatever info
 you have, and I bet someone will be able to track 'em down.
 
 --bb
 

I'd give another $100. -JJR

"Economic Stimulus Act" FTW. Seriously, though, there's GDC. Maybe LLVMDC, too. So while I wouldn't say no to a compiling lib of the backend, is it really needed?
Jul 01 2008
next sibling parent Bill Baxter <dnewsgroup billbaxter.com> writes:
Robert Fraser wrote:
 John Reimer Wrote:
 
 Hello Bill,

 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make it
 freely available freely -- as at least a lib?  It's hard to believe
 anyone would appraise that thing with a high dollar value given its
 less than stellar optimization abilities, and since everyone knows you
 can't make much money off dev tools these days anyway.

 I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing "make
 dmd".

 Or is it more a matter of not being able to find the copyright holders
 in question to ask them?  If so, give us the names and whatever info
 you have, and I bet someone will be able to track 'em down.

 --bb

I'd give another $100. -JJR

"Economic Stimulus Act" FTW. Seriously, though, there's GDC. Maybe LLVMDC, too. So while I wouldn't say no to a compiling lib of the backend, is it really needed?

GDC's problem is that it is not well maintained. LLVMDC's problem is that it just isn't there yet. Until one of the above two situations changes, DMD will be the compiler I actually use. And it's worth at least $100 to me in the mean time to be able to build a working version of the D compiler I actually use. Being able to fix bugs for myself or with the help of the community means at least that much to me. So it's not a question of whether it is "needed". Obviously if it were really needed then none of us would be here on this NG. D would have already failed. It is wanted. And the amount I want it right now is about $100-worth. --bb
Jul 01 2008
prev sibling parent reply John Reimer <terminal.node gmail.com> writes:
Hello Robert,

 John Reimer Wrote:
 
 Hello Bill,
 
 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make
 it freely available freely -- as at least a lib?  It's hard to
 believe anyone would appraise that thing with a high dollar value
 given its less than stellar optimization abilities, and since
 everyone knows you can't make much money off dev tools these days
 anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing
 "make dmd".
 
 Or is it more a matter of not being able to find the copyright
 holders in question to ask them?  If so, give us the names and
 whatever info you have, and I bet someone will be able to track 'em
 down.
 
 --bb
 

-JJR

Seriously, though, there's GDC. Maybe LLVMDC, too. So while I wouldn't say no to a compiling lib of the backend, is it really needed?

LLVMDC is only partially operational. gdc hasn't proven that it can "keep up". They are both very important projects, but having the complete dmd compiler means even more potential for active fixing of elusive bugs in the reference compiler, code generator optimization and updates for more recent instructions sets, improved object file format support on win32 (coff), shared-lib fixes for linux(?), experimentation, improved tool support, compiler embedding, immediate bug hunting expeditions for library developers... and easier distribution of the compiler in general -- many things that Walter doesn't have time to fix. It's not likely to happen even with the economic incentive. But having a completely open reference compiler can mean a lot when it comes to getting D adopted. This has been one of D's major handicaps, I think, for a long time. -JJR
Jul 01 2008
parent reply Robert Fraser <fraserofthenight gmail.com> writes:
John Reimer Wrote:

 Hello Robert,
 
 John Reimer Wrote:
 
 Hello Bill,
 
 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make
 it freely available freely -- as at least a lib?  It's hard to
 believe anyone would appraise that thing with a high dollar value
 given its less than stellar optimization abilities, and since
 everyone knows you can't make much money off dev tools these days
 anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing
 "make dmd".
 
 Or is it more a matter of not being able to find the copyright
 holders in question to ask them?  If so, give us the names and
 whatever info you have, and I bet someone will be able to track 'em
 down.
 
 --bb
 

-JJR

Seriously, though, there's GDC. Maybe LLVMDC, too. So while I wouldn't say no to a compiling lib of the backend, is it really needed?

LLVMDC is only partially operational. gdc hasn't proven that it can "keep up". They are both very important projects, but having the complete dmd compiler means even more potential for active fixing of elusive bugs in the reference compiler, code generator optimization and updates for more recent instructions sets, improved object file format support on win32 (coff), shared-lib fixes for linux(?), experimentation, improved tool support, compiler embedding, immediate bug hunting expeditions for library developers... and easier distribution of the compiler in general -- many things that Walter doesn't have time to fix. It's not likely to happen even with the economic incentive. But having a completely open reference compiler can mean a lot when it comes to getting D adopted. This has been one of D's major handicaps, I think, for a long time. -JJR

It appears I have been officially "pwned" here. You & Bill are right; GDC/LLVMDC isn't sufficient.
Jul 02 2008
next sibling parent John Reimer <terminal.node gmail.com> writes:
Hello Robert,


 

GDC/LLVMDC isn't sufficient.

Well, GDC or LLVMDC might have been the way to go... if Walter were using/developing them as a reference compiler. :) But that is something he apparently cannot do lest he "taint" the code. -JJR
Jul 02 2008
prev sibling parent reply Christopher Wright <dhasenan gmail.com> writes:
Robert Fraser wrote:
 It appears I have been officially "pwned" here. You & Bill are right; 
 GDC/LLVMDC isn't sufficient.

Or we could politely ask Walter to switch to llvm or gcc for the backend for dmd. Hey, he actually changed opEquals to bool...
Jul 02 2008
parent reply John Reimer <terminal.node gmail.com> writes:
Hello Christopher,

 Robert Fraser wrote:
 
 It appears I have been officially "pwned" here. You & Bill are right;
 GDC/LLVMDC isn't sufficient.
 

backend for dmd. Hey, he actually changed opEquals to bool...

Similar has been suggested on several occasions. If you take a peek at previous postings in this group on the topic you will see his answer which invariably is "no" with a short explanation about "tainting" (or something similar). He doesn't want to look at any other compiler code (opensource or otherwise). It's a self-imposed rule to simplify his defense in any potential legal disputes, as I understand it, since he appears to still be in the compiler business. This is completely understandable, but I think it hampers D's progress to some degree. I'm not so sure we can ever get the backend by slapping down some money, but I'd agree that it would be great if something were done... moving to an opensource backend of one sort or another would be extremely good for D. Whether or not our request is successful, the statement made here (about the donation) at least expresses how important it is to this community to see an active opensource backend as part of the reference compiler. But we probably shouldn't get our hopes up too much: the issue hasn't budged one iota for quite a long time. Yet, you never know. :) -JJR
Jul 02 2008
next sibling parent reply Don <nospam nospam.com.au> writes:
John Reimer wrote:
 Hello Christopher,
 
 Robert Fraser wrote:

 It appears I have been officially "pwned" here. You & Bill are right;
 GDC/LLVMDC isn't sufficient.

backend for dmd. Hey, he actually changed opEquals to bool...

Similar has been suggested on several occasions. If you take a peek at previous postings in this group on the topic you will see his answer which invariably is "no" with a short explanation about "tainting" (or something similar). He doesn't want to look at any other compiler code (opensource or otherwise). It's a self-imposed rule to simplify his defense in any potential legal disputes, as I understand it, since he appears to still be in the compiler business. This is completely understandable, but I think it hampers D's progress to some degree. I'm not so sure we can ever get the backend by slapping down some money, but I'd agree that it would be great if something were done... moving to an opensource backend of one sort or another would be extremely good for D. Whether or not our request is successful, the statement made here (about the donation) at least expresses how important it is to this community to see an active opensource backend as part of the reference compiler. But we probably shouldn't get our hopes up too much: the issue hasn't budged one iota for quite a long time. Yet, you never know. :)

IIRC, earlier this year, Walter said he was still trying to get it released, and did expect to be successful eventually. I doubt that the problem has much to do with money. Murky legal issues could well be a major part of it. I recently got some code from my university days open-sourced, and it was extremely painful and slow -- even after getting in-principle agreement from *everyone* who could possibly be a copyright owner, none of them were certain that they had authority to approve its release.
Jul 03 2008
next sibling parent John Reimer <terminal.node gmail.com> writes:
Hello Don,


 IIRC, earlier this year, Walter said he was still trying to get it
 released, and did expect to be successful eventually.

Hmmmm, I must have missed or forgotten that post. That's better news than I expected.
 I doubt that the problem has much to do with money. Murky legal issues
 could well be a major part of it. I recently got some code from my
 university days open-sourced, and it was extremely painful and slow --
 even after getting in-principle agreement from *everyone* who could
 possibly be a copyright owner, none of them were certain that they had
 authority to approve its release.
 

I think a few (now) opensource projects have been that way. OpenWatcom, I think, had a long process of source cleanup and legal preparation/licensing before they could release the code. It's probably the same with Java and OpenSolaris to some degree. -JJR
Jul 03 2008
prev sibling parent BCS <ao pathlink.com> writes:
Reply to don,

 IIRC, earlier this year, Walter said he was still trying to get it
 released, and did expect to be successful eventually.
 
 I doubt that the problem has much to do with money. 

The money still works as a "statement of interest" of sorts and could be used as "incentive" to any reluctant parties.
Jul 03 2008
prev sibling parent reply BCS <ao pathlink.com> writes:
Reply to John,

 Hello Christopher,
 
 Robert Fraser wrote:
 
 It appears I have been officially "pwned" here. You & Bill are
 right; GDC/LLVMDC isn't sufficient.
 

backend for dmd. Hey, he actually changed opEquals to bool...

at previous postings in this group on the topic you will see his answer which invariably is "no" with a short explanation about "tainting" (or something similar). He doesn't want to look at any other compiler code (opensource or otherwise). It's a self-imposed rule to simplify his defense in any potential legal disputes, as I understand it, since he appears to still be in the compiler business. This is completely understandable, but I think it hampers D's progress to some degree. I'm not so sure we can ever get the backend by slapping down some money, but I'd agree that it would be great if something were done... moving to an opensource backend of one sort or another would be extremely good for D. Whether or not our request is successful, the statement made here (about the donation) at least expresses how important it is to this community to see an active opensource backend as part of the reference compiler. But we probably shouldn't get our hopes up too much: the issue hasn't budged one iota for quite a long time. Yet, you never know. :)

We could do it in reverse; compile the GCC backend as a lib, and ship that and the minimal headers to Walter and then he could develop DMD with that without ever seeing a line of (executable) GCC code. He might even be able to build and ship both GCC and DMC versions of DMD.
Jul 03 2008
parent reply Bill Baxter <dnewsgroup billbaxter.com> writes:
BCS wrote:

 We could do it in reverse; compile the GCC backend as a lib, and ship 
 that and the minimal headers to Walter and then he could develop DMD 
 with that without ever seeing a line of (executable) GCC code. He might 
 even be able to build and ship both GCC and DMC versions of DMD.
 

But GCC is GPL so merely linking against it automatically taints the code. Or is the current front end license GPL compatible? --bb
Jul 03 2008
next sibling parent Don <nospam nospam.com.au> writes:
Bill Baxter wrote:
 BCS wrote:
 
 We could do it in reverse; compile the GCC backend as a lib, and ship 
 that and the minimal headers to Walter and then he could develop DMD 
 with that without ever seeing a line of (executable) GCC code. He 
 might even be able to build and ship both GCC and DMC versions of DMD.

But GCC is GPL so merely linking against it automatically taints the code. Or is the current front end license GPL compatible? --bb

Jul 03 2008
prev sibling parent BCS <ao pathlink.com> writes:
Reply to Bill,

 BCS wrote:
 
 We could do it in reverse; compile the GCC backend as a lib, and ship
 that and the minimal headers to Walter and then he could develop DMD
 with that without ever seeing a line of (executable) GCC code. He
 might even be able to build and ship both GCC and DMC versions of
 DMD.
 

code. Or is the current front end license GPL compatible? --bb

even so, wouldn't a .so/.dll get around that?
Jul 05 2008
prev sibling next sibling parent davidl <davidl 126.com> writes:
在 Wed, 02 Jul 2008 11:51:01 +0800,Bill Baxter  
<dnewsgroup billbaxter.com> 写道:

 Robert Fraser wrote:
 John Reimer Wrote:

 Hello Bill,

 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make it
 freely available freely -- as at least a lib?  It's hard to believe
 anyone would appraise that thing with a high dollar value given its
 less than stellar optimization abilities, and since everyone knows you
 can't make much money off dev tools these days anyway.

 I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing "make
 dmd".

 Or is it more a matter of not being able to find the copyright holders
 in question to ask them?  If so, give us the names and whatever info
 you have, and I bet someone will be able to track 'em down.

 --bb

I'd give another $100. -JJR

Seriously, though, there's GDC. Maybe LLVMDC, too. So while I wouldn't say no to a compiling lib of the backend, is it really needed?

GDC's problem is that it is not well maintained. LLVMDC's problem is that it just isn't there yet. Until one of the above two situations changes, DMD will be the compiler I actually use. And it's worth at least $100 to me in the mean time to be able to build a working version of the D compiler I actually use. Being able to fix bugs for myself or with the help of the community means at least that much to me. So it's not a question of whether it is "needed". Obviously if it were really needed then none of us would be here on this NG. D would have already failed. It is wanted. And the amount I want it right now is about $100-worth. --bb

From my point of view, every patches should apply to DMD frontend, so the community gets benefit from it. While the backend dev kit gives the possibility of not *sending* the patch to DMD. The current problem of DMD development is not every patch accepted or reviewed before the next DMD release. Time & partial class is the main problem prevent me from doing some backend related stuff. I hope more people can get involved into this. And make dparser an experiment ground so people can firstly test their willing features in dparser. -- 使用 Opera 革命性的电子邮件客户程序: http://www.opera.com/mail/
Jul 01 2008
prev sibling next sibling parent reply nazo <lovesyao gmail.com> writes:
Also opensource backend will be needed in phobos for runtime assembler 
and runtime D compiling feature :)

Runtime generations:
C# has System.Reflection.Assembly that is runtime assembler.
Xbyak library is runtime assembler for C++.
tcc can be used as runtime C compiler.
but D?

Bill Baxter Wrote:
 It's been talked about before, but exactly how much money do the people 
 who own the copyright to DMD's backend want in order to make it freely 
 available freely -- as at least a lib?  It's hard to believe anyone 
 would appraise that thing with a high dollar value given its less than 
 stellar optimization abilities, and since everyone knows you can't make 
 much money off dev tools these days anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D 
 compiler that anyone can recompile for themselves just by typing "make 
 dmd".
 
 Or is it more a matter of not being able to find the copyright holders 
 in question to ask them?  If so, give us the names and whatever info you 
 have, and I bet someone will be able to track 'em down.
 
 --bb

Jul 02 2008
parent Robert Fraser <fraserofthenight gmail.com> writes:
nazo Wrote:
 Also opensource backend will be needed in phobos for runtime assembler 
 and runtime D compiling feature :)
 
 Runtime generations:
 C# has System.Reflection.Assembly that is runtime assembler.
 Xbyak library is runtime assembler for C++.
 tcc can be used as runtime C compiler.
 but D?

IIRC, Burton Radons was able to do just that... but with the DMD as an executable, not a lib. See: http://www.digitalmars.com/webnews/newsgroups.php?art_group=digitalmars.D.announce&article_id=11436
Jul 02 2008
prev sibling next sibling parent "Koroskin Denis" <2korden gmail.com> writes:
On Wed, 02 Jul 2008 05:03:32 +0400, John Reimer <terminal.node gmail.com>  
wrote:

 Hello Bill,

 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make it
 freely available freely -- as at least a lib?  It's hard to believe
 anyone would appraise that thing with a high dollar value given its
 less than stellar optimization abilities, and since everyone knows you
 can't make much money off dev tools these days anyway.
  I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing "make
 dmd".
  Or is it more a matter of not being able to find the copyright holders
 in question to ask them?  If so, give us the names and whatever info
 you have, and I bet someone will be able to track 'em down.
  --bb

I'd give another $100. -JJR

I would donate $100 for that, too. Not that much for a few man-year project, for we *NEED* that urgently. Plain old .lib file with stripped-off debug symbols and a dmd-only license would do the trick. Please, Walter!
Jul 02 2008
prev sibling next sibling parent "Simen Kjaeraas" <simen.kjaras gmail.com> writes:
Koroskin Denis <2korden gmail.com> wrote:

 On Wed, 02 Jul 2008 05:03:32 +0400, John Reimer  
 <terminal.node gmail.com> wrote:

 Hello Bill,

 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make it
 freely available freely -- as at least a lib?  It's hard to believe
 anyone would appraise that thing with a high dollar value given its
 less than stellar optimization abilities, and since everyone knows you
 can't make much money off dev tools these days anyway.
  I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing "make
 dmd".
  Or is it more a matter of not being able to find the copyright holders
 in question to ask them?  If so, give us the names and whatever info
 you have, and I bet someone will be able to track 'em down.
  --bb

I'd give another $100. -JJR

I would donate $100 for that, too. Not that much for a few man-year project, for we *NEED* that urgently. Plain old .lib file with stripped-off debug symbols and a dmd-only license would do the trick. Please, Walter!

Add another $100 from me. -- Simen
Jul 02 2008
prev sibling next sibling parent Mark Sanders <mark cyanox.nl> writes:
Bill Baxter wrote:
 It's been talked about before, but exactly how much money do the people 
 who own the copyright to DMD's backend want in order to make it freely 
 available freely -- as at least a lib?  It's hard to believe anyone 
 would appraise that thing with a high dollar value given its less than 
 stellar optimization abilities, and since everyone knows you can't make 
 much money off dev tools these days anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D 
 compiler that anyone can recompile for themselves just by typing "make 
 dmd".
 
 Or is it more a matter of not being able to find the copyright holders 
 in question to ask them?  If so, give us the names and whatever info you 
 have, and I bet someone will be able to track 'em down.
 
 --bb

If this is going to happen I'll be happy to spend 100 euro (~$157) or more. -- Mark Sanders.
Jul 02 2008
prev sibling next sibling parent BCS <ao pathlink.com> writes:
Reply to Bill,

 It's been talked about before, but exactly how much money do the
 people who own the copyright to DMD's backend want in order to make it
 freely available freely -- as at least a lib?  It's hard to believe
 anyone would appraise that thing with a high dollar value given its
 less than stellar optimization abilities, and since everyone knows you
 can't make much money off dev tools these days anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D
 compiler that anyone can recompile for themselves just by typing "make
 dmd".
 
 Or is it more a matter of not being able to find the copyright holders
 in question to ask them?  If so, give us the names and whatever info
 you have, and I bet someone will be able to track 'em down.
 
 --bb
 

I'd chip in somthing, $20 at least, maybe more, can't say exactly how much right now... (man I whish Marx hadn't been wrong).
Jul 02 2008
prev sibling next sibling parent BLS <nanali nospam-wanadoo.fr> writes:
Bill Baxter schrieb:
 It's been talked about before, but exactly how much money do the people 
 who own the copyright to DMD's backend want in order to make it freely 
 available freely -- as at least a lib?  It's hard to believe anyone 
 would appraise that thing with a high dollar value given its less than 
 stellar optimization abilities, and since everyone knows you can't make 
 much money off dev tools these days anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D 
 compiler that anyone can recompile for themselves just by typing "make 
 dmd".
 
 Or is it more a matter of not being able to find the copyright holders 
 in question to ask them?  If so, give us the names and whatever info you 
 have, and I bet someone will be able to track 'em down.
 
 --bb

Jul 04 2008
prev sibling next sibling parent JAnderson <ask me.com> writes:
Bill Baxter wrote:
 It's been talked about before, but exactly how much money do the people 
 who own the copyright to DMD's backend want in order to make it freely 
 available freely -- as at least a lib?  It's hard to believe anyone 
 would appraise that thing with a high dollar value given its less than 
 stellar optimization abilities, and since everyone knows you can't make 
 much money off dev tools these days anyway.
 
 I'd happily chip in $100 US if it meant finally having an official D 
 compiler that anyone can recompile for themselves just by typing "make 
 dmd".
 
 Or is it more a matter of not being able to find the copyright holders 
 in question to ask them?  If so, give us the names and whatever info you 
 have, and I bet someone will be able to track 'em down.
 
 --bb

If it where just about money a donation button could be put on the digitalmars website and every other D website, with a target (whatever unreachable number that is). It would only transfer the amount across when that amount was reached. I'd give 100. -Joel
Jul 05 2008
prev sibling parent reply "Manfred_Nowak" <svv1999 hotmail.com> writes:
Bill Baxter wrote:

 I'd happily chip in $100 US

Because there are some and might be even more donators: http://www.fundable.com/ -manfred -- Maybe some knowledge of some types of disagreeing and their relation can turn out to be useful: http://blog.createdebate.com/2008/04/07/writing-strong-arguments/
Jul 12 2008
parent reply Bill Baxter <dnewsgroup billbaxter.com> writes:
Manfred_Nowak wrote:
 Bill Baxter wrote:
 
 I'd happily chip in $100 US

Because there are some and might be even more donators: http://www.fundable.com/ -manfred

That sounds pretty neat. Would be cooler if they made their money by advertising instead of taking a 10% cut. 10% seems like a lot for doing something that seems rather simple. --bb
Jul 12 2008
parent "Manfred_Nowak" <svv1999 hotmail.com> writes:
Bill Baxter wrote:

 10% seems like a lot for doing 
 something that seems rather simple.
 

They claim to be professionals and therefore are likely to know that simplicity, which may result in an openness for negotiation _before_ starting anything on their platform. Because they require goals as low as low 200$, close to 20$ should do for any amount. -manfred -- Maybe some knowledge of some types of disagreeing and their relation can turn out to be useful: http://blog.createdebate.com/2008/04/07/writing-strong-arguments/
Jul 13 2008