LSPModeler Class¶

class LSPModeler¶

Modeler environment. Main class of the modeler library which enables the creation and manipulation of a virtual machine that can load and execute programs written in the LSP language.

See:	`localsolver::LocalSolver`
See:	`LSPModule`
Since:	10.0

Summary¶

Functions¶
`LSPModeler`	Constructs a complete modeler environment.
`~LSPModeler`	Deletes this modeler environment and all associated objects.
`createSolver`	Returns a new LocalSolver instance that can be used to launch a module with the method LSPModule::run().
`getModule`	Returns the module with the given name.
`addModuleLookupPath`	Adds a new lookup path for modules.
`clearModuleLookupPaths`	Deletes all paths used to search for modules.
`loadModule`	Loads the module written in LSP at the indicated location.
`createModule`	Creates an empty module with the given name.
`createFunction`	Creates an external LSPFunction.
`createFunction`	Creates an external LSPFunction.
`createMap`	Creates an LSPMap.
`createNil`	Creates a nil value.
`createInt`	Creates an integer value.
`createDouble`	Creates a double value.
`createBool`	Creates a boolean value.
`createString`	Creates a string value.

Functions¶

LSPModeler::LSPModeler()¶

Constructs a complete modeler environment.

See:	`localsolver::LocalSolver`

LSPModeler::~LSPModeler()¶: Deletes this modeler environment and all associated objects. This also includes solvers created using the LSPModeler::createSolver() method.

LocalSolver LSPModeler::createSolver()¶

Returns a new LocalSolver instance that can be used to launch a module with the method LSPModule::run().

Returns:	Solver.
See:	`localsolver::LocalSolver`

LSPModule LSPModeler::getModule(const std::string &moduleName)¶

Returns the module with the given name. User modules can be accessed as well as builtin modules like the JSON module or the CSV module. If the module is not loaded, this method attempts to load it from the paths specified by LSPModule::addModuleLookupPath().

The variables of the module can then be manipulated through the associated LSPModule object.

Parameters:	moduleName – Module name.
Returns:	Module loaded.
See:	`LSPModule`

void LSPModeler::addModuleLookupPath(const std::string &path)¶

Adds a new lookup path for modules. The paths specified when calling this method are taken into account when the LSP virtual machine loads a module, either by a direct call to the LSPModule::getModule() method, or indirectly when loading a dependency to another module. By default, the lookup path contains at least the current runtime folder.

Parameters:	path – New path to consider for modules.

void LSPModeler::clearModuleLookupPaths()¶

Deletes all paths used to search for modules. This method deletes all the paths previously added by LSPModule::addModuleLookupPath() method, as well as the default location(s) (including the current execution folder).

__Important note:__ after calling this method, you must at least add a path with LSPModule::addModuleLookupPath(). Without a path, you won’t be able to load any LSP modules other than the native ones supplied by the virtual machine.

LSPModule LSPModeler::loadModule(const std::string &moduleName, const std::string &filePath)¶

Loads the module written in LSP at the indicated location. The loaded module will take the name specified in parameter. Unlike LSPModule::getModule(), this method ignores all paths indicated by LSPModule::addModuleLookupPath(), and if a module with a similar name is already loaded, an exception will be thrown.

Once loaded, the variables of the module can be manipulated through the associated LSPModule object.

Parameters:	moduleName – Name taken by the module once loaded. filePath – Path to the module file.
Returns:	Module created.
See:	`LSPModule`

LSPModule LSPModeler::createModule(const std::string &moduleName)¶

Creates an empty module with the given name. The variables of the module can then be manipulated through the associated LSPModule object.

Parameters:	moduleName – Module name.
Returns:	Module created.
See:	`LSPModule`

LSPFunction LSPModeler::createFunction(LSPFunctor *functor)¶

Creates an external LSPFunction. The argument must be derived from LSPFunctor. When the function is called, the modeler instance will be made accessible to the function, as well as the arguments.

For instance, the following example creates a simple function that accepts two arguments and returns the sum of both values. The generated function is then exposed in an LSP module under the name “myCustomFunction”:

class MyCustomFunction : public LSPFunctor {
    LSPValue call(LSPModeler& modeler, const LSPValue* args, int nbArgs) override {
        return modeler.createDouble(arguments[0].asDouble() + arguments[1].asDouble());
    }
};

MyCustomFunction customFunctor;
module.setFunction("myCustomFunction", modeler.createFunction(&customFunctor));

Note: This method should only be used to expose functions used during the modeling process. You should not use this method to create a function that will be used during the resolution as anexternal function. In this case, you should instead use the solver API directly (see localsolver::LSExternalFunction)

Parameters:	functor – Implementation of the external function.
Returns:	Function created.
See:	`LSPFunctor`
See:	`LSPFunction`

LSPFunction LSPModeler::createFunction(const std::string &name, LSPFunctor *functor)¶

Creates an external LSPFunction. The argument must be derived from LSPFunctor. When the function is called, the modeler instance will be made accessible to the function, as well as the arguments.

For instance, the following example creates a simple function that accepts two arguments and returns the sum of both values. The generated function is then exposed in an LSP module under the name “myCustomFunction”:

class MyCustomFunction : public LSPFunctor {
    LSPValue call(LSPModeler& modeler, const LSPValue* arguments, int nbArguments) override {
        return modeler.createDouble(arguments[0].asDouble() + arguments[1].asDouble());
    }
};

MyCustomFunction customFunctor;
module.setFunction("myCustomFunction", modeler.createFunction("myCustomFunction", &customFunctor));

Note: This method should only be used to expose functions used during the modeling process. You should not use this method to create a function that will be used during the resolution as an external function. In this case, you should instead use the solver API directly (see localsolver::LSExternalFunction)

Parameters:	name – Name of the function. The name is only used to identify the function in the generated stack trace when an exception occurs. Once created, the function can be associated with any variable in any module, regardless of its name. functor – Implementation of the external function.
Returns:	Function created.
See:	`LSPFunctor`
See:	`LSPFunction`

LSPMap LSPModeler::createMap()¶

Creates an LSPMap. A map is a data structure mapping keys to values that can also be used as an array-like structure. Keys and values can be of any type except nil. The map can be assigned to any variable in a module with LSPModule::setMap() or can be part of another map with LSPMap::setMap().

Returns:	Map created.
See:	`LSPMap`

LSPValue LSPModeler::createNil()¶

Creates a nil value.

Returns:	Created nil value.
See:	`LSPValue`

LSPValue LSPModeler::createInt(lsint value)¶

Creates an integer value. The value can be assigned to any variable in a module with LSPModule::setValue() or can be part of a map as key or value.

Returns:	Created integer value.
See:	`LSPValue`

LSPValue LSPModeler::createDouble(lsdouble value)¶

Creates a double value. The value can be assigned to any variable in a module with LSPModule::setValue() or can be part of a map as key or value.

Returns:	Created double value.
See:	`LSPValue`

LSPValue LSPModeler::createBool(bool value)¶

Creates a boolean value. Please note that there is no dedicated type for booleans in the modeler. They are simulated with integers: 1 denotes true and 0 denotes false. The created value can be assigned to any variable in a module with LSPModule::setValue() or can be part of a map as key or value.

Returns:	Created boolean value.
See:	`LSPValue`

LSPValue LSPModeler::createString(const std::string &value)¶

Creates a string value. The value can be assigned to any variable in a module with LSPModule::setValue() or can be part of a map as key or value.

Returns:	Created string value.
See:	`LSPValue`