Function
quiet — quiet “missing” errors
Synopsis
quiet(val: any) -> any
Description
The quiet function returns its argument val unless val is
error("missing"), in which case it returns error("quiet").
Various operators and functions treat quiet errors differently than
missing errors, in particular, dropping them instead of propagating them.
Quiet errors are ignored by operators aggregate, cut, and values.
Examples
A quiet error in values produces no output
# spq
values quiet(this)
# input
error("missing")
# expected output
Without quiet, values produces the missing error
# spq
values this
# input
error("missing")
# expected output
error("missing")
The cut operator drops quiet errors but retains missing errors
# spq
cut b:=x+1,c:=quiet(x+1),d:=quiet(a+1)
# input
{a:1}
# expected output
{b:error("missing"),d:2}