🚀 go-pugleaf

On page 252 of the tex book the assignment \voffset=2\baselineskip
seems to multiply a glue parameter by the constant 2 and assign to
a dimen parameter.  On the other hand, on page 208 a similar-looking
assignment, containing the string "=0\fullypaid" concatenates a
"0" to \fullypaid, to possibly get 021 if \fullypaid evaluates to "21".

The question is: when do we get implicit multiplication, and when
do we get concatenation?  I assume that if we jam together a digit
and a <glue parameter> it multiplies them, but I can't find any
discussion of this.

For example, the assignment \voffset=2\baselineskip is apparently
of the form <dimen parameter> <equals> <integer constant> <glue parameter>.
This form is not one of those given as a legal assignment on page 276.

Alan Wendt