ExpressionParser Class Reference

#include <expression_parser.h>

Public Member Functions
	ExpressionParser (const ExpressionParser &)=delete
ExpressionParser &	operator= (const ExpressionParser &)=delete
void	set_function (const std::string &js_function) const
void	set_expressions (const std::string &parameters, const std::string &expr_x, const std::string &expr_y, const std::string &expr_z)
int	parameter_count () const
double	get_scalar (double arg) const
Eigen::Vector3d	get_vector (double arg) const
Eigen::Vector3d	get_vector (const Eigen::Ref< Eigen::Vector3d > arg) const
Eigen::Vector3d	get_vector (const Eigen::Ref< Eigen::Vector3d > position, const std::vector< std::string > &regions) const

Private Member Functions
void	die_if_error (duk_int_t err) const
double	get_vector_component (int idx) const
Eigen::Vector3d	compute_vector (int argument_count) const

Private Attributes
duk_context *	ctx

Detailed Description

This class handles a JavaScript function that computes either a scalar or a 3D vector, which depends on either a single parameter t, or on (x, y, z), or (x, y, z, regions).

Member Function Documentation

compute_vector()

Eigen::Vector3d ExpressionParser::compute_vector ( int  argument_count ) const

private

Compute a vector. This must be called after duk_dup(ctx, -1) and one or more calls to duk_push_number(). argument_count should match the number of arguments pushed.

die_if_error()

void ExpressionParser::die_if_error ( duk_int_t  err ) const

private

Abort with an suitable error message if err is an actual error, in which case the top of the stack is assumed to hold the corresponding Error object.

get_scalar()

double ExpressionParser::get_scalar

(

double

arg

)

const

Compute a scalar from the given scalar argument.

get_vector() [1/3]

Eigen::Vector3d ExpressionParser::get_vector

(

const Eigen::Ref< Eigen::Vector3d >

arg

)

const

Compute a vector from the given vector argument.

get_vector() [2/3]

Eigen::Vector3d ExpressionParser::get_vector	(	const Eigen::Ref< Eigen::Vector3d >	position,
		const std::vector< std::string > &	regions
	)		const

Compute a vector from the given vector and array of strings arguments.

get_vector() [3/3]

Eigen::Vector3d ExpressionParser::get_vector

(

double

arg

)

const

Compute a vector from the given scalar argument.

get_vector_component()

double ExpressionParser::get_vector_component ( int  idx ) const

private

Get the given component from the array at the top of the stack. Preserve the stack state.

parameter_count()

int ExpressionParser::parameter_count ( ) const

inline

Return the number of parameters of the JavaScript function.

set_expressions()

void ExpressionParser::set_expressions	(	const std::string &	parameters,
		const std::string &	expr_x,
		const std::string &	expr_y,
		const std::string &	expr_z
	)

Use the provided expressions for the x, y and z components for subsequent computations of vectors. parameters should be a comma-separated list of parameter names, typically "t" or "x,y,z".

set_function()

void ExpressionParser::set_function

(

const std::string &

js_function

)

const

Use the provided JavaScript function expression for subsequent computations. The provided function should take either one, three or four numeric parameters, and return either a number or an array of three numbers.

Member Data Documentation

ctx

duk_context* ExpressionParser::ctx

private

Ducktape context holding the internal state of the interpreter.

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The documentation for this class was generated from the following files:

• expression_parser.h
• expression_parser.cpp