Class astutedds::dcps::FilterExpression

ClassList > astutedds > dcps > FilterExpression

Parsed filter expression.

• #include <content_filtered_topic.hpp>

Public Functions

Type	Name
	FilterExpression () = default
	FilterExpression (const std::string & expression, const std::vector< std::string > & parameter_names={}) Parse SQL-like filter expression.
const std::string &	error_message () const Get parse error message if invalid.
bool	evaluate (const SampleType & sample, std::function< FilterValue(const SampleType &, const std::string &)> get_field) const Evaluate filter against data sample.
const std::string &	expression_string () const Get the original expression string.
bool	is_valid () const Check if expression is valid.
const std::vector< std::string > &	parameters () const Get parameter values.
void	set_parameter (size_t index, const std::string & value) Set parameter value.

Public Functions Documentation

function FilterExpression [1/2]

astutedds::dcps::FilterExpression::FilterExpression () = default

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function FilterExpression [2/2]

Parse SQL-like filter expression.

explicit astutedds::dcps::FilterExpression::FilterExpression (
    const std::string & expression,
    const std::vector< std::string > & parameter_names={}
) 

Parameters:

• expression Filter expression string (e.g., "x > 5 AND color = 'RED'")
• parameter_names Names for %0, %1 style parameters

Exception:

• std::invalid_argument if expression is invalid

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function error_message

Get parse error message if invalid.

inline const std::string & astutedds::dcps::FilterExpression::error_message () const

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function evaluate

Evaluate filter against data sample.

template<typename SampleType>
bool astutedds::dcps::FilterExpression::evaluate (
    const SampleType & sample,
    std::function< FilterValue (const SampleType &, const std::string &)> get_field
) const

Parameters:

• get_field Function to get field value from sample

Returns:

true if sample passes filter

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function expression_string

Get the original expression string.

inline const std::string & astutedds::dcps::FilterExpression::expression_string () const

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function is_valid

Check if expression is valid.

inline bool astutedds::dcps::FilterExpression::is_valid () const

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function parameters

Get parameter values.

inline const std::vector< std::string > & astutedds::dcps::FilterExpression::parameters () const

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function set_parameter

Set parameter value.

void astutedds::dcps::FilterExpression::set_parameter (
    size_t index,
    const std::string & value
) 

Parameters:

• index Parameter index (0-based)
• value New value

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The documentation for this class was generated from the following file include/astutedds/dcps/content_filtered_topic.hpp