Whether value is a slug id as the schema's $defs/SlugId defines it:
lowercase Unicode letters and digits in hyphen-separated runs, 1 to
SLUG_ID_MAX_LENGTH characters. Characters are code points, as the
schema counts them: a letter outside the Basic Multilingual Plane is one
character, although String.length counts it as two (engine#205).
Anything that is not a string is not.
Whether
valueis a slug id as the schema's$defs/SlugIddefines it: lowercase Unicode letters and digits in hyphen-separated runs, 1 toSLUG_ID_MAX_LENGTHcharacters. Characters are code points, as the schema counts them: a letter outside the Basic Multilingual Plane is one character, althoughString.lengthcounts it as two (engine#205). Anything that is not a string is not.