We do not support keyword arguments as flow inputs, so while this shouldn't work, the error message should ideally indicate that keyword argument is not supported. Instead:
(~>> (2 1 3 #:key values) (sort <))
; :476:0: ~>>: expected one of these literal symbols: `sep' or `△'
; at: (sort <)
; in: (~>> (2 1 3 #:key values) (sort <))
; Source locations:
; :476:26
It looks like this is happening because it is trying to match the first (error-catching) clause in the ~>> macro definition, for some reason, and complains that it doesn't match(?):
qi-lib/threading.rkt:
(define-syntax-parser %~>>
[(_ (arg0 arg ...+) (~or* (~datum sep) (~datum △)) clause:clause ...)
;; catch a common usage error
(report-syntax-error this-syntax
"(~>> (arg ...) flo ...)"
"Attempted to separate multiple values."
"Note that the inputs to ~>> must be wrapped in parentheses.")]
[(_ args:subject clause:clause ...)
#:with ags (attribute args.args)
#'(on ags (~>> clause ...))])
... i.e. it is failing to match on line 2, not the correct second clause on line 8.
We do not support keyword arguments as flow inputs, so while this shouldn't work, the error message should ideally indicate that keyword argument is not supported. Instead:
It looks like this is happening because it is trying to match the first (error-catching) clause in the
~>>macro definition, for some reason, and complains that it doesn't match(?):... i.e. it is failing to match on line 2, not the correct second clause on line 8.