javascript - Easiest way to check subproperty exists -

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• in javascript, there easier way check if property of property exists? 7 answers

i want var = b.c.d || null

but issue is, a might undefined, b might be, or c might be

so short of ugly try{} catch{} or if statements best way this? constructing quite large object (say 50 odd properties) 3rd party data source

var = ( b && b.c && ('d' in b.c)) ? b.c.d : null;