c# - Elvis operator in a casting invocation chain -

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the elvis operator, aka null-conditional operator, massively cool.

in linq queries works great in concert null-coalescing "??" operator.

somedata.where(dt=>(dt?.inner?.innermost?.include=="yes")??false);

but do if need cast intermediate values?

for 1 link in chain, works out fine.

somedata.where(dt=>(      ((innerclass)dt?.inner)      ?.innermost)?.include=="yes")      ??false);

but additional necessary casts cast , invocation "driven apart".

somedata.where(dt=>(      ((innermostclass)            <=== cast      ((innerclass)dt?.inner)      ?.innermost)?.include=="yes"))         <=== use      ??false);

probably messed the parenthesis more once here, hope idea.

though "trainwreck" invocation chain code smell, there more expressive way of doing improve succinctness , clarity?

you can keep chaining , prevent parenthesis using simple extension method:

dt?.inner.as<innerclass>()?.innermost.as<innermostclass>()?.include == "yes"

with extension method defined this:

public static class objectextensions {     public static t as<t>(this object obj) t : class     {         return obj t;     } }

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