Struct clingo_sys::clingo_ground_program_observer

#[repr(C)]
pub struct clingo_ground_program_observer {
    pub init_program: Option<unsafe extern "C" fn(_: bool, _: *mut c_void) -> bool>,
    pub begin_step: Option<unsafe extern "C" fn(_: *mut c_void) -> bool>,
    pub end_step: Option<unsafe extern "C" fn(_: *mut c_void) -> bool>,
    pub rule: Option<unsafe extern "C" fn(_: bool, _: *const clingo_atom_t, _: usize, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub weight_rule: Option<unsafe extern "C" fn(_: bool, _: *const clingo_atom_t, _: usize, _: clingo_weight_t, _: *const clingo_weighted_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub minimize: Option<unsafe extern "C" fn(_: clingo_weight_t, _: *const clingo_weighted_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub project: Option<unsafe extern "C" fn(_: *const clingo_atom_t, _: usize, _: *mut c_void) -> bool>,
    pub output_atom: Option<unsafe extern "C" fn(_: clingo_symbol_t, _: clingo_atom_t, _: *mut c_void) -> bool>,
    pub output_term: Option<unsafe extern "C" fn(_: clingo_symbol_t, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub output_csp: Option<unsafe extern "C" fn(_: clingo_symbol_t, _: c_int, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub external: Option<unsafe extern "C" fn(_: clingo_atom_t, _: clingo_external_type_t, _: *mut c_void) -> bool>,
    pub assume: Option<unsafe extern "C" fn(_: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub heuristic: Option<unsafe extern "C" fn(_: clingo_atom_t, _: clingo_heuristic_type_t, _: c_int, _: c_uint, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub acyc_edge: Option<unsafe extern "C" fn(_: c_int, _: c_int, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub theory_term_number: Option<unsafe extern "C" fn(_: clingo_id_t, _: c_int, _: *mut c_void) -> bool>,
    pub theory_term_string: Option<unsafe extern "C" fn(_: clingo_id_t, _: *const c_char, _: *mut c_void) -> bool>,
    pub theory_term_compound: Option<unsafe extern "C" fn(_: clingo_id_t, _: c_int, _: *const clingo_id_t, _: usize, _: *mut c_void) -> bool>,
    pub theory_element: Option<unsafe extern "C" fn(_: clingo_id_t, _: *const clingo_id_t, _: usize, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>,
    pub theory_atom: Option<unsafe extern "C" fn(_: clingo_id_t, _: clingo_id_t, _: *const clingo_id_t, _: usize, _: *mut c_void) -> bool>,
    pub theory_atom_with_guard: Option<unsafe extern "C" fn(_: clingo_id_t, _: clingo_id_t, _: *const clingo_id_t, _: usize, _: clingo_id_t, _: clingo_id_t, _: *mut c_void) -> bool>,
}

An instance of this struct has to be registered with a solver to observe ground directives as they are passed to the solver.

Note: This interface is closely modeled after the aspif format. For more information please refer to the specification of the aspif format.

Not all callbacks have to be implemented and can be set to NULL if not needed. If one of the callbacks in the struct fails, grounding is stopped. If a non-recoverable clingo API call fails, a callback must return false. Otherwise ::clingo_error_unknown should be set and false returned.

@see clingo_control_register_observer()

Fields

init_program: Option<unsafe extern "C" fn(_: bool, _: *mut c_void) -> bool>

Called once in the beginning.

If the incremental flag is true, there can be multiple calls to @ref clingo_control_solve().

Parameters:

• incremental whether the program is incremental
• data user data for the callback

Returns whether the call was successful

begin_step: Option<unsafe extern "C" fn(_: *mut c_void) -> bool>

Marks the beginning of a block of directives passed to the solver.

@see @ref end_step

Parameters:

• data user data for the callback

Returns whether the call was successful

end_step: Option<unsafe extern "C" fn(_: *mut c_void) -> bool>

Marks the end of a block of directives passed to the solver.

This function is called before solving starts.

@see @ref begin_step

Parameters:

• data user data for the callback

Returns whether the call was successful

rule: Option<unsafe extern "C" fn(_: bool, _: *const clingo_atom_t, _: usize, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>

Observe rules passed to the solver.

Parameters:

• choice determines if the head is a choice or a disjunction
• head the head atoms
• head_size the number of atoms in the head
• body the body literals
• body_size the number of literals in the body
• data user data for the callback

Returns whether the call was successful

weight_rule: Option<unsafe extern "C" fn(_: bool, _: *const clingo_atom_t, _: usize, _: clingo_weight_t, _: *const clingo_weighted_literal_t, _: usize, _: *mut c_void) -> bool>

Observe weight rules passed to the solver.

Parameters:

• choice determines if the head is a choice or a disjunction
• head the head atoms
• head_size the number of atoms in the head
• lower_bound the lower bound of the weight rule
• body the weighted body literals
• body_size the number of weighted literals in the body
• data user data for the callback

Returns whether the call was successful

minimize: Option<unsafe extern "C" fn(_: clingo_weight_t, _: *const clingo_weighted_literal_t, _: usize, _: *mut c_void) -> bool>

Observe minimize constraints (or weak constraints) passed to the solver.

Parameters:

• priority the priority of the constraint
• literals the weighted literals whose sum to minimize
• size the number of weighted literals
• data user data for the callback

Returns whether the call was successful

project: Option<unsafe extern "C" fn(_: *const clingo_atom_t, _: usize, _: *mut c_void) -> bool>

Observe projection directives passed to the solver.

Parameters:

• atoms the atoms to project on
• size the number of atoms
• data user data for the callback

Returns whether the call was successful

output_atom: Option<unsafe extern "C" fn(_: clingo_symbol_t, _: clingo_atom_t, _: *mut c_void) -> bool>

Observe shown atoms passed to the solver. \note Facts do not have an associated aspif atom. The value of the atom is set to zero.

Parameters:

• symbol the symbolic representation of the atom
• atom the aspif atom (0 for facts)
• data user data for the callback

Returns whether the call was successful

output_term: Option<unsafe extern "C" fn(_: clingo_symbol_t, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>

Observe shown terms passed to the solver.

Parameters:

• symbol the symbolic representation of the term
• condition the literals of the condition
• size the size of the condition
• data user data for the callback

Returns whether the call was successful

output_csp: Option<unsafe extern "C" fn(_: clingo_symbol_t, _: c_int, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>

Observe shown csp variables passed to the solver.

Parameters:

• symbol the symbolic representation of the variable
• value the value of the variable
• condition the literals of the condition
• size the size of the condition
• data user data for the callback

Returns whether the call was successful

external: Option<unsafe extern "C" fn(_: clingo_atom_t, _: clingo_external_type_t, _: *mut c_void) -> bool>

Observe external statements passed to the solver.

Parameters:

• atom the external atom
• type the type of the external statement
• data user data for the callback

Returns whether the call was successful

assume: Option<unsafe extern "C" fn(_: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>

Observe assumption directives passed to the solver.

Parameters:

• literals the literals to assume (positive literals are true and negative literals false for the next solve call)
• size the number of atoms
• data user data for the callback

Returns whether the call was successful

heuristic: Option<unsafe extern "C" fn(_: clingo_atom_t, _: clingo_heuristic_type_t, _: c_int, _: c_uint, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>

Observe heuristic directives passed to the solver.

Parameters:

• atom the target atom
• type the type of the heuristic modification
• bias the heuristic bias
• priority the heuristic priority
• condition the condition under which to apply the heuristic modification
• size the number of atoms in the condition
• data user data for the callback

Returns whether the call was successful

acyc_edge: Option<unsafe extern "C" fn(_: c_int, _: c_int, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>

Observe edge directives passed to the solver.

Parameters:

• node_u the start vertex of the edge
• node_v the end vertex of the edge
• condition the condition under which the edge is part of the graph
• size the number of atoms in the condition
• data user data for the callback

Returns whether the call was successful

theory_term_number: Option<unsafe extern "C" fn(_: clingo_id_t, _: c_int, _: *mut c_void) -> bool>

Observe numeric theory terms.

Parameters:

• term_id the id of the term
• number the value of the term
• data user data for the callback

Returns whether the call was successful

theory_term_string: Option<unsafe extern "C" fn(_: clingo_id_t, _: *const c_char, _: *mut c_void) -> bool>

Observe string theory terms.

Parameters:

• term_id the id of the term
• name the value of the term
• data user data for the callback

Returns whether the call was successful

theory_term_compound: Option<unsafe extern "C" fn(_: clingo_id_t, _: c_int, _: *const clingo_id_t, _: usize, _: *mut c_void) -> bool>

Observe compound theory terms.

The name_id_or_type gives the type of the compound term: - if it is -1, then it is a tuple - if it is -2, then it is a set - if it is -3, then it is a list - otherwise, it is a function and name_id_or_type refers to the id of the name (in form of a string term)

Parameters:

• term_id the id of the term
• name_id_or_type the name or type of the term
• arguments the arguments of the term
• size the number of arguments
• data user data for the callback

Returns whether the call was successful

theory_element: Option<unsafe extern "C" fn(_: clingo_id_t, _: *const clingo_id_t, _: usize, _: *const clingo_literal_t, _: usize, _: *mut c_void) -> bool>

Observe theory elements.

Parameters:

• element_id - the id of the element
• terms - the term tuple of the element
• terms_size - the number of terms in the tuple
• condition - the condition of the elemnt
• condition_size - the number of literals in the condition
• data user data for the callback

Returns whether the call was successful

theory_atom: Option<unsafe extern "C" fn(_: clingo_id_t, _: clingo_id_t, _: *const clingo_id_t, _: usize, _: *mut c_void) -> bool>

Observe theory atoms without guard.

Parameters:

• atom_id_or_zero the id of the atom or zero for directives
• term_id the term associated with the atom
• elements the elements of the atom
• size the number of elements
• data user data for the callback

Returns whether the call was successful

theory_atom_with_guard: Option<unsafe extern "C" fn(_: clingo_id_t, _: clingo_id_t, _: *const clingo_id_t, _: usize, _: clingo_id_t, _: clingo_id_t, _: *mut c_void) -> bool>

Observe theory atoms with guard.

Parameters:

• atom_id_or_zero the id of the atom or zero for directives
• term_id the term associated with the atom
• elements the elements of the atom
• size the number of elements
• operator_id the id of the operator (a string term)
• right_hand_side_id the id of the term on the right hand side of the atom
• data user data for the callback

Returns whether the call was successful

Trait Implementations

impl Debug for clingo_ground_program_observer

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Copy for clingo_ground_program_observer

impl Clone for clingo_ground_program_observer

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.