accept @pure @nothrow @return attributes

[Jonathan Marler via Digitalmars-d]

On Monday, 26 January 2015 at 22:09:44 UTC, Walter Bright wrote:
> On 1/26/2015 1:25 PM, Jonathan Marler wrote:
>> The lexer would recognize these attributes as normal ID 
>> tokens. The grammar
>> could be amended to allow a function to be decorated with 
>> keywords and generic
>> id tokens.  Then the meaning of those tokens would be handled 
>> by semantic
>> analysis.
>
> Not going to do that.
>
>> So the result would be that the lexer would see "nogc" and 
>> "safe" as
>> normal id tokens (not keywords) which would be consumed as 
>> function attributes
>> by the grammar.  As far as I can tell this results in the best 
>> of both worlds.
>> We can omit the '@' character on function attributes like safe 
>> and nogc but they
>> don't have to be added as keywords.
>
> I strongly dislike context sensitive tokens, whether or not 
> they are done by the lexer or the parser or the semantic 
> analysis.
>
> It's like using a nail for a cotter pin.
Walter I hate to waste your time in answering my silly questions. 
  I know you have a much deeper knowledge and understanding of the 
language then I.  I can see that you believe my suggestion would 
create some unnecessary complexity ("It's like using a nail for a 
cotter pin"), however, I can't see how it would so I'm going to 
ask another question. I can see that you are trying to save time 
from your short responses so I'll understand if I understand if 
you feel I'm a lost cause and do not respond again.

You said you strongly dislike "context-sensitive" tokens but I 
still don't know exactly what you mean by "context-sensitive".  
You said a token is "context-sensitive" if it is "A keyword in 
one context and an identifier in another".  However, since I'm 
not proposing that "save" and "nogc" be keywords in any context, 
this doesn't appear to fall under your definition.  So I must 
assume your real definition is more general. However, if the 
definition is too general then couldn't you consider almost any 
token "context-sensitive".  For example, the token "static" or 
"ref" have different meanings depending on their context, so are 
they "context-sensitive"?  Yes they are still keyword tokens, but 
"safe" and "nogc" would still just be regular id tokens so what 
makes "safe" and "nogc" more "context-sensitive" then "static" 
and "ref"?

I'm honestly trying to understand.  I can see from how the 
grammar works that you don't agree my solution is a good one, but 
I'm failing to understand why.  I fail to see how allowing a 
function to be decorated with id tokens is more complex then only 
allowing keywords.  Also sorry for harping on definitions,  I 
majored in Computer Science and Mathematics...having strict 
definitions comes from my days of writing endless proofs.