• NAME ErrorHandler
• DESCRIPTION
• METHODS
• clearText()
• appendText(string s)
• internalError(string msg, string rest)
• syntaxError(string msg, string current, string rest)
• semanticError(string msg, string current, string rest)

NAME ErrorHandler

This class handles errors, primarily by reporting and dying! Only one ErrorHandler is permitted since this class contains class-dependent variables (i.e., it should not be instantiated).

DESCRIPTION

Various kinds of errors are detected during query evaluation, methods in this class support processing of those errors. In general, all errors should end up here rather than croaking or dying in the underlying methods.

METHODS

clearText()

Clear the accumulated text from the class.

appendText(string s)

• s
  
- The string to append to the accumulated text.

Adds text to the accumulated text, used to remember where in the parsed text the program currently is.

internalError(string msg, string rest)

• msg
  
- The message to print.
• rest
  
- The rest of the program.

Some internal error was detected due to a bug in the compiler, print something appropriate and die.

syntaxError(string msg, string current, string rest)

• msg
  
- The message to print.
• current
  
- The current token.
• rest
  
- The rest of the program.

A syntax error was detected. Print something appropriate and die.

semanticError(string msg, string current, string rest)

• msg
  
- The message to print.
• current
  
- The current token.
• rest
  
- The rest of the program.

A semantic error was detected. Print something appropriate and die.