On Dec 29, 2008, at 00:17 , Jun Young Kim wrote:

> irb(main):006:0> a.send(:!=, 2)
> SyntaxError: compile error
> (irb):6: syntax error, unexpected tNEQ, expecting tSTRING_CONTENT or  
> tSTRING_DBEG or tSTRING_DVAR or tSTRING_END
> a.send(:!=, 2)
>         ^
> 	from (irb):6
> 	from :0
>
> As you see, ruby can recognize a != as a tNEG(not equals).

no. you're getting a syntax error because :!= is not a valid symbol,  
but :"!=" is. Try that and you'll see that there is no such method.