libdap++ Updated for version 3.8.2
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Evaluate a constraint expression.
#include <ConstraintEvaluator.h>
Classes | |
struct | function |
Public Types | |
typedef std::vector< Clause * > ::const_iterator | Clause_citer |
typedef std::vector< Clause * > ::iterator | Clause_iter |
typedef std::vector< BaseType * > ::const_iterator | Constants_citer |
typedef std::vector< BaseType * > ::iterator | Constants_iter |
typedef std::list< function > ::const_iterator | Functions_citer |
typedef std::list< function > ::iterator | Functions_iter |
Public Member Functions | |
void | append_clause (int op, rvalue *arg1, rvalue_list *arg2) |
Add a clause to a constraint expression. | |
void | append_clause (bool_func func, rvalue_list *args) |
Add a clause to a constraint expression. | |
void | append_clause (btp_func func, rvalue_list *args) |
Add a clause to a constraint expression. | |
void | append_constant (BaseType *btp) |
bool | boolean_expression () |
Does the current constraint expression return a boolean value? | |
Clause_iter | clause_begin () |
Clause_iter | clause_end () |
bool | clause_value (Clause_iter &i, DDS &dds) |
ConstraintEvaluator () | |
BaseType * | eval_function (DDS &dds, const string &dataset) |
Evaluate a function-valued constraint expression. | |
DDS * | eval_function_clauses (DDS &dds) |
Evaluate a function-valued constraint expression that contains several function calls. | |
DataDDS * | eval_function_clauses (DataDDS &dds) |
Evaluate a function-valued constraint expression that contains several function calls. Takes and returns a DataDDS. | |
bool | eval_selection (DDS &dds, const string &dataset) |
Evaluate a boolean-valued constraint expression. This is main method for the evaluator ans is called by the BaseType::serialize() methods. | |
bool | function_clauses () |
Does the current constraint expression return a DDS pointer? | |
bool | functional_expression () |
Does the current constraint expression return a BaseType pointer? This method does not evaluate the clause, it provides information to the evaluator regarding _how_ to evaluate the clause. | |
void | parse_constraint (const string &constraint, DDS &dds) |
Parse the constraint expression given the current DDS. | |
virtual | ~ConstraintEvaluator () |
External Function Accessors | |
The Constraint Evaluator carries with it a list of external functions it can use while evaluate a constraint expression. If a constraint contains any of these functions, the entries in the list allow the parser to evaluate it. The functions are of three types: those that return boolean values, those that return real (also called BaseType) values, and those that are applied during evaluation of the projection for side effect
These methods are used to manipulate this list of known external functions. | |
void | add_function (const string &name, bool_func f) |
Add a boolean function to the list. | |
void | add_function (const string &name, btp_func f) |
Add a BaseType function to the list. | |
void | add_function (const string &name, proj_func f) |
Add a projection function to the list. | |
bool | find_function (const string &name, bool_func *f) const |
Find a Boolean function with a given name in the function list. | |
bool | find_function (const string &name, btp_func *f) const |
Find a BaseType function with a given name in the function list. | |
bool | find_function (const string &name, proj_func *f) const |
Find a projection function with a given name in the function list. | |
Friends | |
class | func_name_is |
Definition at line 46 of file ConstraintEvaluator.h.
typedef std::vector<Clause *>::const_iterator libdap::ConstraintEvaluator::Clause_citer |
Definition at line 90 of file ConstraintEvaluator.h.
typedef std::vector<Clause *>::iterator libdap::ConstraintEvaluator::Clause_iter |
Definition at line 91 of file ConstraintEvaluator.h.
typedef std::vector<BaseType *>::const_iterator libdap::ConstraintEvaluator::Constants_citer |
Definition at line 93 of file ConstraintEvaluator.h.
typedef std::vector<BaseType *>::iterator libdap::ConstraintEvaluator::Constants_iter |
Definition at line 94 of file ConstraintEvaluator.h.
typedef std::list<function>::const_iterator libdap::ConstraintEvaluator::Functions_citer |
Definition at line 96 of file ConstraintEvaluator.h.
typedef std::list<function>::iterator libdap::ConstraintEvaluator::Functions_iter |
Definition at line 97 of file ConstraintEvaluator.h.
libdap::ConstraintEvaluator::ConstraintEvaluator | ( | ) |
Definition at line 49 of file ConstraintEvaluator.cc.
References libdap::register_functions().
libdap::ConstraintEvaluator::~ConstraintEvaluator | ( | ) | [virtual] |
Definition at line 54 of file ConstraintEvaluator.cc.
void libdap::ConstraintEvaluator::add_function | ( | const string & | name, |
bool_func | f | ||
) |
Definition at line 197 of file ConstraintEvaluator.cc.
References func_name_is.
Referenced by libdap::register_functions().
void libdap::ConstraintEvaluator::add_function | ( | const string & | name, |
btp_func | f | ||
) |
Definition at line 206 of file ConstraintEvaluator.cc.
References func_name_is.
void libdap::ConstraintEvaluator::add_function | ( | const string & | name, |
proj_func | f | ||
) |
Definition at line 215 of file ConstraintEvaluator.cc.
References func_name_is.
void libdap::ConstraintEvaluator::append_clause | ( | bool_func | func, |
rvalue_list * | args | ||
) |
This function adds a boolean function clause to the constraint expression.
func | A pointer to a boolean function from the list of supported functions. |
args | A list of arguments to that function. |
Definition at line 125 of file ConstraintEvaluator.cc.
void libdap::ConstraintEvaluator::append_clause | ( | btp_func | func, |
rvalue_list * | args | ||
) |
This function adds a real-valued (BaseType) function clause to the constraint expression.
func | A pointer to a BaseType function from the list of supported functions. |
args | A list of arguments to that function. |
Definition at line 142 of file ConstraintEvaluator.cc.
void libdap::ConstraintEvaluator::append_clause | ( | int | op, |
rvalue * | arg1, | ||
rvalue_list * | arg2 | ||
) |
This function adds an operator clause to the constraint expression.
op | An integer indicating the operator in use. These values are generated by bison . |
arg1 | A pointer to the argument on the left side of the operator. |
arg2 | A pointer to a list of the arguments on the right side of the operator. |
Definition at line 108 of file ConstraintEvaluator.cc.
void libdap::ConstraintEvaluator::append_constant | ( | BaseType * | btp | ) |
The Constraint Evaluator maintains a list of BaseType pointers for all the constants that the constraint expression parser generates. These objects are deleted by the Constraint Evaluator destructor. Note that there are no list accessors; these constants are never accessed from the list. The list is simply a convenient way to make sure the constants are disposed of properly.
Definition at line 157 of file ConstraintEvaluator.cc.
bool libdap::ConstraintEvaluator::boolean_expression | ( | ) |
Definition at line 392 of file ConstraintEvaluator.cc.
ConstraintEvaluator::Clause_iter libdap::ConstraintEvaluator::clause_begin | ( | ) |
Returns the first clause in a parsed constraint expression.
Definition at line 70 of file ConstraintEvaluator.cc.
ConstraintEvaluator::Clause_iter libdap::ConstraintEvaluator::clause_end | ( | ) |
Returns a reference to the end of the list of clauses in a parsed constraint expression. It does not reference the last clause
Definition at line 78 of file ConstraintEvaluator.cc.
bool libdap::ConstraintEvaluator::clause_value | ( | Clause_iter & | iter, |
DDS & | dds | ||
) |
Returns the value of the indicated clause of a constraint expression.
Definition at line 86 of file ConstraintEvaluator.cc.
Definition at line 288 of file ConstraintEvaluator.cc.
References libdap::Clause::value().
Referenced by libdap::DODSFilter::send_data(), and libdap::DODSFilter::send_data_ddx().
Definition at line 367 of file ConstraintEvaluator.cc.
References libdap::DDS::add_var(), libdap::DDS::get_dataset_name(), libdap::DDS::get_factory(), libdap::DataDDS::get_protocol(), libdap::DataDDS::get_version(), libdap::BaseType::set_send_p(), and libdap::Clause::value().
This method can be called for any function-valued constraint expression. Unlike eval_function(), it will package the return value in a new DDS object. The server should free this object once it has been serialized and sent.
Definition at line 341 of file ConstraintEvaluator.cc.
References libdap::DDS::add_var(), libdap::DDS::get_dataset_name(), libdap::DDS::get_factory(), libdap::BaseType::set_send_p(), and libdap::Clause::value().
Referenced by libdap::DODSFilter::send_data(), and libdap::DODSFilter::send_data_ddx().
bool libdap::ConstraintEvaluator::eval_selection | ( | DDS & | dds, |
const string & | dataset | ||
) |
dds | Use these variables when evaluating the expressions. |
dataset | This string is passed to the read() methods. |
Definition at line 414 of file ConstraintEvaluator.cc.
References DBG.
Referenced by libdap::Sequence::read_row(), libdap::Vector::serialize(), libdap::UInt32::serialize(), libdap::UInt16::serialize(), libdap::Structure::serialize(), libdap::Str::serialize(), libdap::Int32::serialize(), libdap::Int16::serialize(), libdap::Grid::serialize(), libdap::Float64::serialize(), libdap::Float32::serialize(), and libdap::Byte::serialize().
bool libdap::ConstraintEvaluator::find_function | ( | const string & | name, |
proj_func * | f | ||
) | const |
Definition at line 256 of file ConstraintEvaluator.cc.
bool libdap::ConstraintEvaluator::find_function | ( | const string & | name, |
bool_func * | f | ||
) | const |
Definition at line 224 of file ConstraintEvaluator.cc.
bool libdap::ConstraintEvaluator::find_function | ( | const string & | name, |
btp_func * | f | ||
) | const |
Definition at line 240 of file ConstraintEvaluator.cc.
bool libdap::ConstraintEvaluator::function_clauses | ( | ) |
This method does not evaluate the clauses, it provides information to the evaluator regarding _how_ to evaluate the clause.
Definition at line 311 of file ConstraintEvaluator.cc.
References libdap::Clause::value_clause().
Referenced by libdap::DODSFilter::send_data(), and libdap::DODSFilter::send_data_ddx().
bool libdap::ConstraintEvaluator::functional_expression | ( | ) |
Definition at line 277 of file ConstraintEvaluator.cc.
References libdap::Clause::value_clause().
Referenced by libdap::DODSFilter::send_data(), libdap::DODSFilter::send_data_ddx(), libdap::DODSFilter::send_dds(), and libdap::DODSFilter::send_ddx().
void libdap::ConstraintEvaluator::parse_constraint | ( | const string & | constraint, |
DDS & | dds | ||
) |
Evaluate the constraint expression; return the value of the expression. As a side effect, mark the DDS so that BaseType's mfuncs can be used to correctly read the variable's value and send it to the client.
constraint | A string containing the constraint expression. |
dds | The DDS that provides the environment within which the constraint is evaluated. |
Throws | Error if the constraint does not parse. |
Definition at line 450 of file ConstraintEvaluator.cc.
References ce_expr_delete_buffer(), ce_expr_string(), ce_expr_switch_to_buffer(), and ce_exprparse().
Referenced by libdap::DODSFilter::send_data(), libdap::DODSFilter::send_data_ddx(), libdap::DODSFilter::send_dds(), and libdap::DODSFilter::send_ddx().
friend class func_name_is [friend] |
Definition at line 87 of file ConstraintEvaluator.h.
Referenced by add_function().