/// <summary>
/// Parses a macro.
/// </summary>
/// <param name="inputText">The macro script text.</param>
/// <returns>The parse tree, starting with the InstructionSet node.</returns>
/// <exception cref="ParseException">Thrown if the text cannot be parsed.</exception>
public static ParseTree ParseMacro(string inputText)
{
if (inputText == null)
{
throw new ArgumentNullException();
}
// Preparse ‘ ’ quotes. Given that macros are entered in Word, and that people get confused, it's easier to just treat them all the same.
inputText = inputText.Replace('‘', '\'');
inputText = inputText.Replace('’', '\'');
// Parse macro
ExpressionGrammar grammar = _grammarPool.GetObject();
try
{
var parser = new Parser(grammar);
parser.Parse(inputText);
// Check for macro errors
ParseTree parseTree = parser.Context.CurrentParseTree;
grammar.CheckParseTreeOk(parseTree);
return(parseTree);
}
finally
{
_grammarPool.PutObject(grammar);
}
}
/// <summary>
/// Singleton instance of grammar.
/// Thread-safe. Grammar is verified on first access.
/// </summary>
private static ExpressionGrammar CreateGrammar()
{
var grammar = new ExpressionGrammar(true);
// Verify the grammar on first load
var parser = new Parser(grammar);
var errors = parser.Language.Errors;
if (errors.Count > 0)
{
throw new Exception("Internal error: macro grammar contains error(s): " + string.Join("\n", errors));
}
return(grammar);
}
/// <summary>
/// Prewarm the grammar pool with one object.
/// </summary>
public static void Prewarm()
{
ExpressionGrammar grammar = _grammarPool.GetObject();
_grammarPool.PutObject(grammar);
}
