internal static ExpressionBase Parse(PositionalTokenizer tokenizer, int line = 0, int column = 0)
{
SkipWhitespace(tokenizer);
var dict = new DictionaryExpression();
while (tokenizer.NextChar != '}')
{
var key = ExpressionBase.ParseClause(tokenizer);
if (key.Type == ExpressionType.ParseError)
{
return(key);
}
SkipWhitespace(tokenizer);
if (tokenizer.NextChar != ':')
{
ParseError(tokenizer, "Expecting colon following key expression");
break;
}
tokenizer.Advance();
SkipWhitespace(tokenizer);
var value = ExpressionBase.ParseClause(tokenizer);
if (value.Type == ExpressionType.ParseError)
{
break;
}
dict.Entries.Add(new DictionaryExpression.DictionaryEntry {
Key = key, Value = value
});
SkipWhitespace(tokenizer);
if (tokenizer.NextChar == '}')
{
break;
}
if (tokenizer.NextChar != ',')
{
ParseError(tokenizer, "Expecting comma between entries");
break;
}
tokenizer.Advance();
SkipWhitespace(tokenizer);
}
tokenizer.Advance();
return(dict);
}
/// <summary>
/// Gets the next expression from the input.
/// </summary>
/// <returns>The next expression, <c>null</c> if at end of file.</returns>
public static ExpressionBase Parse(PositionalTokenizer tokenizer)
{
SkipWhitespace(tokenizer);
if (tokenizer.NextChar == '\0')
{
return(new ParseErrorExpression("Unexpected end of script", tokenizer.Line, tokenizer.Column, tokenizer.Line, tokenizer.Column));
}
var line = tokenizer.Line;
var column = tokenizer.Column;
var clause = ExpressionBase.ParseClause(tokenizer);
if (clause.Type == ExpressionType.ParseError || clause.Type == ExpressionType.Comment)
{
return(clause);
}
var clauseEndLine = tokenizer.Line;
var clauseEndColumn = tokenizer.Column;
SkipWhitespace(tokenizer);
var joinerLine = tokenizer.Line;
var joinerColumn = tokenizer.Column;
switch (tokenizer.NextChar)
{
case '+':
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Add, joinerLine, joinerColumn);
break;
case '-':
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Subtract, joinerLine, joinerColumn);
break;
case '*':
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Multiply, joinerLine, joinerColumn);
break;
case '/':
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Divide, joinerLine, joinerColumn);
break;
case '%':
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Modulus, joinerLine, joinerColumn);
break;
case '=':
tokenizer.Advance();
if (tokenizer.NextChar == '=')
{
tokenizer.Advance();
clause = ParseComparison(tokenizer, clause, ComparisonOperation.Equal, joinerLine, joinerColumn);
}
else
{
clause = ParseAssignment(tokenizer, clause, joinerLine, joinerColumn);
}
break;
case '!':
tokenizer.Advance();
if (tokenizer.NextChar != '=')
{
clause = ParseError(tokenizer, "= expected following !", joinerLine, joinerColumn);
}
else
{
tokenizer.Advance();
clause = ParseComparison(tokenizer, clause, ComparisonOperation.NotEqual, joinerLine, joinerColumn);
}
break;
case '<':
tokenizer.Advance();
if (tokenizer.NextChar == '=')
{
tokenizer.Advance();
clause = ParseComparison(tokenizer, clause, ComparisonOperation.LessThanOrEqual, joinerLine, joinerColumn);
}
else
{
clause = ParseComparison(tokenizer, clause, ComparisonOperation.LessThan, joinerLine, joinerColumn);
}
break;
case '>':
tokenizer.Advance();
if (tokenizer.NextChar == '=')
{
tokenizer.Advance();
clause = ParseComparison(tokenizer, clause, ComparisonOperation.GreaterThanOrEqual, joinerLine, joinerColumn);
}
else
{
clause = ParseComparison(tokenizer, clause, ComparisonOperation.GreaterThan, joinerLine, joinerColumn);
}
break;
case '&':
tokenizer.Advance();
if (tokenizer.NextChar != '&')
{
clause = ParseError(tokenizer, "& expected following &", joinerLine, joinerColumn);
}
else
{
tokenizer.Advance();
clause = ParseConditional(tokenizer, clause, ConditionalOperation.And, joinerLine, joinerColumn);
if (clause.Type == ExpressionType.ParseError)
{
return(clause);
}
}
break;
case '|':
tokenizer.Advance();
if (tokenizer.NextChar != '|')
{
clause = ParseError(tokenizer, "| expected following |", joinerLine, joinerColumn);
}
else
{
tokenizer.Advance();
clause = ParseConditional(tokenizer, clause, ConditionalOperation.Or, joinerLine, joinerColumn);
if (clause.Type == ExpressionType.ParseError)
{
return(clause);
}
}
break;
default:
if (clause.EndColumn == 0)
{
clause.EndLine = clauseEndLine;
clause.EndColumn = clauseEndColumn;
}
return(clause);
}
clause = clause.Rebalance();
Debug.Assert(clause.Line != 0);
Debug.Assert(clause.Column != 0);
Debug.Assert(clause.EndLine != 0);
Debug.Assert(clause.EndColumn != 0);
return(clause);
}
