Errors may occur when converting Prolog terms to Python objects as
defined in section 2. These errors are
reported as
instantiation_error, type_error(Type, Culprit)
or
domain_error(Domain, Culprit).
Defined domains are:
- py_constant
- In a term
@(Constant), Constant is not true,
false or none. For example, py_call(print(@error)).
- py_keyword_arg
- In a call to Python, a non keyword argument follows a keyword argument.
For example,
py_call(m:f(1,x=2,3), R)
- py_string_as
- The value for a
py_string_as(As) option is invalid. For
example, py_call(m:f(), R, [py_string_as(float)])
- py_dict_as
- The value for a
py_dict_as(As) option is invalid. For
example, py_call(m:f(), R, [py_dict_as(list)])
- py_term
- A term being translated to Python is unsupported. For example,
py_call(m:f(point(1,2)), R).
Defined types are:
- py_object
- A Python object reference was expected. For example,
py_free(42)
- rational
- A Python
fraction instance is converted to a Prolog
rational number, but the textual conversion does not produce a valid
rational number. This can happen if the Python fraction is
subclassed and the __str__() method does not produce
a correct string.
- py_key_value
- Inside a
{k:v, ...} representation for a dictionary we find
a term that is not a key-value pair. For example,
py_call(m:f({a:1, x}), R)
- py_set
- Inside a
py_set(Elements), Elements is not a
list. For example, py_call(m:f(py_set(42)), R).
- py_target
- In
py_call(Target:FuncOrAttrOrMethod), Target is
not a module (atom) or Python object reference. For example, py_call(7:f(),
R).
- py_callable
- In
py_call(Target:FuncOrAttrOrMethod), FuncOrAttrOrMethod
is not an atom or compound. For example, py_call(m:7, R).
