Please elaborate.

instead of "search over syntax", something more specific like

    "text, wildcard or regex search" 

over (as an example)

    "stackoverflow, standard library, langauge spec for cpython, 
    400 most popular libs on github/pip/package index/ (whatever)"

e.g. here's a search engine for scala that lets you use type signatures: http://scalex.org/

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really useful search engine, just needs clarification on the database contents and what kinds of searches you can do.