thytype_abbrev
Parse.thytype_abbrev : {Name:string,Thy:string} * hol_type * bool -> unit
Abbreviates a type to a specific theory-qualified name.
A call to thytype_abbrev({Name=n,Thy=t}, ty, prp) establishes the
"kernel" name t$n as an abbreviation for the type ty, as happens
with type_abbrev. The boolean flag prp indicates whether or not this
abbreviation will also be used when the printer comes to print the given
type. In other words, after the call it becomes possible to write
“:args t$n” to stand for type ty. If there are type variables in
ty they become the parameters to the new abbreviated type operator.
These parameters need to be filled in in the args position above. If
there are no type variables in ty then abbreviation is of a whole
type, and args must be blank.
If there was an existing abbreviation for t$n, then this will be
replaced by the call.
In addition, after the given call, this abbreviation will become the
preferred binding for the bare name n. Other abbreviations in
different theories will need to use the form with fully-qualified names
(thy1$n, thy2$n etc).
If the boolean flag is false, this invocation is comparable to the
behaviour after intputonly_type_abbrev: the abbreviation can be used
to input types of the desired pattern, but such types will print as they
did previously.
Failure
Fails if ty is a variable type.
Comments
As with other parsing and pretty-printing functions, there is a
companion function, temp_thytype_abbrev, which has the same effect on
the global grammar but does not cause the change to persist when the
theory is exported.
It is legitimate to use a string for the theory component of the record that does not correspond to the current theory. Indeed, it is perfectly reasonable to do this, if one wants to give priority to a particular ancestral abbreviation.