Often I try to test some Wolfram Language (WL) expression within Wolfram|Alpha (Just the standard Web-Interface or WinPhone App). Its hopeless concerning use of WL and structuring expressions. Some few WL-expressions are understood. Most of them are not understood. Always it ends up in an endless trial and error process, since WA does not understand what I mean.
Unfortunately there is no Wolfram|Alpha documentation since it claims to be self-explaining. But it is very far from that. Is there some link where I can at least learn how to use WL within Wolfram|Alpha?
I can enter
Subsets[{1,2,3,4,5},{3}]
I can enter as well
Union[{{1,2,3},{2,3,4}},{{3,4,5}}]
But I cannot enter
Union[Subsets[{1,2,3,4,5},{3}],{{3,4,5}}]
This is misunderstood.
Of course I tried the same with natural language input. Something like
(subsets of {1,2,3,4,5} with size 3) union {{3,4,5}}
Simply said, you can’t (generally speaking) use wolfram language directly. Though it would be easy to change wolfram alpha to accept Wolfram Language code. ToExpression[input] basically it could be ‘hazardous’ as you easily do infinite computations or computations that delete files or connect to other computers or run other commands.
Generally I would not recommend to use W|A to learn WL…
Of course I do not use W|A to learn WL. I use Programming Lab for that. But W|A is handsome for getting some quick answers on small problems. But it’s really tedious since it’s unpredictable what W|A understands and what it doesn’t understand.
Accepting WL-expressions within W|A seems natural to me. And some of them are accepted in deed. Your “hazardous”-argument does not convince me. Of course you can do stupid things with each and every programming language.