identifier is the type of the identifier stored in the table. It is meant to be associated with a string

The type of the table

This exception can be raised when some identifier or some symbol is not found in a query

empty is an empty table

find_id_of_sym sym t returns the identifier of the string sym stored in t. Raises Not_found if no such identifier exists.

find_sym_from_id id t returns the string (i.e. the symbol) corresponding to the identifier id in table t

add_sym sym t returns a pair (id,t') where id is the identifier associated with sym in t'. If sym already was in t then t'=t and id is the identifier which it was associated with. Otherwise, a new identifier is generated and the new association is stored in t'.

to_string t outputs the table t in a string.

log_content level t logs the content of table t.

fold f table a returns f id1 sym1 (f id2 sym2 ( ... ( f idN symN a) ... )) where the (id,sym) pairs are the ones that are stored in the table table. The order of these key-value pairs in the table is unspecified.