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Utilities

Vl-plural-p

(vl-plural-p x) determines whether a description of a list should be plural instead of singluar.

Signature
(vl-plural-p x) → *

Output sometimes needs to be customized depending on whether a list contains only one element or many elements, e.g.,

Warning: foo, bar, and baz are mismatched socks, vs.
Warning: foo is a mismatched sock.

(vl-plural-p x) is a stupid function to distinguish between the cases. It returns true for a list like (foo bar baz) with more than one element, or false for a list like (foo) with exactly one element.

We consider lists that have no elements to be plural. This gives the proper behavior in cases like:

0 warnings to report,
1 warning to report,
2 warnings to report,
...

Definitions and Theorems

Function: vl-plural-p$inline

(defun vl-plural-p$inline (x)
  (declare (xargs :guard t))
  (let ((__function__ 'vl-plural-p))
    (declare (ignorable __function__))
    (mbe :logic (not (equal (len x) 1))
         :exec (or (atom x) (not (atom (cdr x)))))))