CoCoA » CoCoA-5

Withing CoCoA-5 (TeX and html version are OK)
this is the list I get for ? Commands and Functions for STRING: RingElem (among others) is missing. Why?

? operators, shortcuts -- Special characters equivalent to commands
? ascii -- convert between characters and ascii code
? error -- throw an error message
? fold -- inset newlines into a long string
? FoldToListInput -- convert string so it looks like a list of short strings
? GetEnv -- access shell variables
? IsIn -- check if one object is contained in another
? len -- the length of an object
? max -- a maximum element of a sequence or list
? min -- a minimum element of a sequence or list
? OpenIFile -- open input file
? OpenIString -- open input string
? OpenOFile -- open output file
? OpenSocket -- open a socket connection
? package -- keyword marking content of a CoCoA package
? PackageOf -- package of an identifier
? PlayCantStop -- First game in CoCoA
? protect -- protect a variable from being overwritten
? source -- read commands from a file or device
? starting -- list functions starting with a given string
? substring -- substring of a string
? SymbolRange -- range of symbols for the indeterminates of a PolyRing
? SystemCommand -- run a system command