ReQL command: bracket
Command syntax
sequence.bracket(attr) → sequence singleSelection.bracket(attr) → value object.bracket(attr) → value array.bracket(index) → value
Description
Get a single field from an object. If called on a sequence, gets that field from every object in the sequence, skipping objects that lack it.
Under most circumstances, you’ll want to use getField (or its shorthand
g
) or nth rather thanbracket
. Thebracket
term may be useful in situations where you are unsure of the data type returned by the term you are callingbracket
on.
Example: What was Iron Man’s first appearance in a comic?
r.table("marvel").get("IronMan").bracket("firstAppearance").run(conn);
// more idiomatically:
r.table("marvel").get("IronMan").g("firstAppearance").run(conn);
The bracket
command also accepts integer arguments as array offsets, like the nth command.
Example: Get the fourth element in a sequence. (The first element is position 0
, so the fourth element is position 3
.)
r.expr(r.array(10, 20, 30, 40, 50)).bracket(3).run(conn);
// more idiomatically:
r.expr(r.array(10, 20, 30, 40, 50)).nth(3).run(conn);
40
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