How to check if element exists in array with jq

The semantics of ‘contains’ is not straightforward at all. In general, it would be better to use ‘index’ to test if an array has a specific value, e.g.

.fruit | index( "orange" )

However, if the item of interest is itself an array, the general form:

 ARRAY | index( [ITEM] )

should be used, e.g.:

[1, [2], 3] | index( [[2]] )  #=> 1


If your jq has IN/1 then a better solution is to use it:

.fruit as $f | "orange" | IN($f[])

If your jq has first/1 (as does jq 1.5), then here is a fast definition of IN/1 to use:

def IN(s): first((s == .) // empty) // false;


Another efficient alternative that is sometimes more convenient is to use any/2, e.g.

any(.fruit[]; . == "orange")

or equivalently:

any(.fruit[] == "orange"; .)

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