ExprContext Class Reference

#include <Expression.h>

List of all members.

---

Detailed Description

Context for use in generating an expression from an AST.

Before parsing an expression, create an ExprContext to describe the context in which the expression will be evaluated.

Currently, the only property of an ExprContext is a single TupleDescription describing a tuple that will be available to an expression when it is evaluated.

Public Member Functions
TupleDescription	getTupleDescription () const
	Get the description of the input tuple to the expression.
void	setTupleDescription (TupleDescription desc)
	Set the description of the input tuple to the expression.
void	getNamedTupleInfo (string name, TupleDescription &desc, unsigned int &index) const
	Get the description of a named input tuple, and the index of that tuple in the input.
void	setNamedTupleInfo (string name, TupleDescription desc, unsigned int index)
	Set the description and index of a named input tuple.
void	findFieldName (string field_name, string &tuple_name, unsigned int &tuple_index, TupleDescription &tuple_desc, unsigned int &field_index) const throw ( ExprException )
	Find a field with a particular name.
Static Public Member Functions
const string	to_string (DataType t)

---

Member Function Documentation

void ExprContext::findFieldName (  string  field_name, string &  tuple_name, unsigned int &  tuple_index, TupleDescription &  tuple_desc, unsigned int &  field_index )  const throw ( ExprException )

Find a field with a particular name. Exceptions: ExprException  if it doesn't find exactally one field.

void ExprContext::getNamedTupleInfo (  string  name, TupleDescription &  desc, unsigned int &  index )  const

Get the description of a named input tuple, and the index of that tuple in the input.

TupleDescription ExprContext::getTupleDescription (   )  const

Get the description of the input tuple to the expression. Returns: an empty TupleDescription if no description was ever provided

void ExprContext::setNamedTupleInfo (  string  name, TupleDescription  desc, unsigned int  index )

Set the description and index of a named input tuple.

void ExprContext::setTupleDescription (  TupleDescription  desc  )

Set the description of the input tuple to the expression.

const string ExprContext::to_string (  DataType  t  )  [static]

---

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

• Expression.h

---