Extends the support for terms in the SWI-Prolog standard library.

 ascii_id(-Id:atom) is det

 ascii_id(+Term:term, -Id:atom) is det

Generates an Id for the given Prolog term. The Id is guarantee to only contain ASCII letter and digits to ensure that it can be used by many programs.

Prolog terms can contain many characters and can have arbitrary size. For these reasons, this predicate generates the Id based on the MD5 hash of a serialization of the given Prolog term.

MD5 hashes sometimes start with an ASCII digit, which is not supported in some languages/context (for example, the DOT language does not allow IDs to start with a digit). For this reason, an arbitrary ASCII letter is prefixed at the beginning of the Id.

 compound_arguments(+Term:term, -Arguments:list(term)) is det

 compound_arity(+Term:term, -Arity:nonneg) is det

 compound_name(+Term:term, +Name:atom) is semidet

compound_name(+Term:term, -Name:atom) is det

 number_of_variables(+Term:term, -NumberOfVariables:nonneg) is det

 replace_blobs(+Term1, -Term2) is det

Copy Term1 to Term2, replacing non-text blobs. This is required for error messages that may hold streams and other handles to non-readable objects.

 shared_vars(+Terms:list(term), -SharedVariables:ordset(var)) is det

 shared_vars(+Term1:term, +Term2:term, -SharedVariables:ordset(var)) is det

 write_fact(@Term) is det

 write_term(@Term) is det

Alternative to write_canonical/[1,2] that lives up to the promise that "terms written with this predicate can always be read back".