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Re: Lightweight syntax: a dissident view

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On 2010年11月26日 21:10:10 +0200, Mark Hamburg <mark@grubmah.com> wrote:
At the risk of having accusations of Perlishness flung around, there's also the option of just optimizing the single-parameter, single-expression case and introducing a token like $ which essentially turns anything it touches into a function with spreading "contamination": 
	$ --> function( x ) return x end
	$ + 1 --> function( x ) return x + 1 end
	( $ + 1 ) * $ --> function( x ) return ( x + 1 ) * x end
	$ - x --> function( y ) return y - x end

Too tricky. One must arbitrarily chose where to stop contamination in the
grammar. Consider:
 ? --> return some_proxy_obj[function( x ) return x end]
 ? --> return function( x ) return some_proxy_obj[x] end
? --> return function( x ) return math.sin(x) end, function return math.cos(x) end 
 ? --> return function( x ) return math.sin(x), math.cos(x) end
Note that ... token already stands for "arguments".
So if 'return' in expression context would define anonymous vararg function, 
greedily matching comma separated list of expressions
(this is the second time I try to push this idea, because it looks
very cute), then your examples could look like:
$ --> return (...)
$ + 1 --> return ... + 1
( $ + 1 ) * $ --> (return ( ... + 1 ) * ...)
$ - x --> return ... - x

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