Issue 4133: Give predicate ly:grob-properties? the description "grob properties"

    \set Staff.InstrumentName = "Test"

previously led to

    warning: type check for `InstrumentName' failed;
    value `"Test"' must be of type `ly:grob-properties'

and will now instead produce

    warning: type check for `InstrumentName' failed;
    value `"Test"' must be of type `grob properties'.

The output looks slightly less cryptic and more intentional.  The plural
form is indeed correct: this type of context property serves as a
container for _all_ grob properties of InstrumentName.

diff --git a/scm/lily.scm b/scm/lily.scm
index 793ca901fee8d45850e78351d0bca6f2ea70dd9f..3ba26bc6dc6eece709b3714ec9e300a41311f46b 100644 (file)
--- a/scm/lily.scm
+++ b/scm/lily.scm
@@ -693,6 +693,7 @@ messages into errors.")
     (,ly:font-metric? . "font metric")
     (,ly:grob? . "graphical (layout) object")
     (,ly:grob-array? . "array of grobs")
+    (,ly:grob-properties? . "grob properties")
     (,ly:input-location? . "input location")
     (,ly:item? . "item")
     (,ly:iterator? . "iterator")