/// <summary>
/// Parses an anonymous function definition in the format "(a) => body" or "(a) { body }"
/// </summary>
public static ExpressionBase ParseAnonymous(PositionalTokenizer tokenizer)
{
var name = CreateAnonymousFunctionName(tokenizer.Line, tokenizer.Column);
var function = new AnonymousUserFunctionDefinitionExpression(name);
function.Location = new TextRange(tokenizer.Line, tokenizer.Column, 0, 0);
return(function.Parse(tokenizer));
}
/// <summary>
/// Parses an anonymous function definition in the format "a => body" where <paramref name="parameter"/>
/// is "a" and <paramref name="tokenizer"/> is pointing at "body".
/// </summary>
public static ExpressionBase ParseAnonymous(PositionalTokenizer tokenizer, ExpressionBase parameter)
{
var variable = parameter as VariableExpression;
if (variable == null)
{
return(new ParseErrorExpression("Cannot create anonymous function from " + parameter.Type));
}
var name = CreateAnonymousFunctionName(parameter.Location.Start.Line, parameter.Location.Start.Column);
var function = new AnonymousUserFunctionDefinitionExpression(name);
function.Location = parameter.Location;
function.Parameters.Add(new VariableDefinitionExpression(variable.Name, variable.Location.Start.Line, variable.Location.Start.Column));
return(function.ParseShorthandBody(tokenizer));
}
private static ExpressionBase ParseClauseCore(PositionalTokenizer tokenizer)
{
ExpressionBase clause;
switch (tokenizer.NextChar)
{
case '!':
tokenizer.Advance();
clause = ParseClause(tokenizer);
if (clause.Type == ExpressionType.ParseError)
{
return(clause);
}
return(new ConditionalExpression(null, ConditionalOperation.Not, clause));
case '(':
if (AnonymousUserFunctionDefinitionExpression.IsAnonymousParameterList(tokenizer))
{
return(AnonymousUserFunctionDefinitionExpression.ParseAnonymous(tokenizer));
}
tokenizer.Advance();
clause = ExpressionBase.Parse(tokenizer);
if (clause.Type == ExpressionType.ParseError)
{
return(clause);
}
if (tokenizer.NextChar != ')')
{
if (tokenizer.NextChar == '\0')
{
return(ParseError(tokenizer, "No closing parenthesis found"));
}
return(ParseError(tokenizer, "Expected closing parenthesis, found: " + tokenizer.NextChar));
}
clause.IsLogicalUnit = true;
tokenizer.Advance();
return(clause);
case '"':
try
{
var stringValue = tokenizer.ReadQuotedString().ToString();
return(new StringConstantExpression(stringValue));
}
catch (InvalidOperationException ex)
{
return(ParseError(tokenizer, ex.Message));
}
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
return(ParseNumber(tokenizer, true));
case '-':
var tokenStart = tokenizer.Location;
tokenizer.Advance();
if (tokenizer.NextChar >= '0' && tokenizer.NextChar <= '9')
{
var result = ParseNumber(tokenizer, false);
var tokenEnd = result.Location.End;
switch (result.Type)
{
case ExpressionType.IntegerConstant:
result = new IntegerConstantExpression(-((IntegerConstantExpression)result).Value);
break;
case ExpressionType.FloatConstant:
result = new FloatConstantExpression(-((FloatConstantExpression)result).Value);
break;
default:
return(result);
}
result.Location = new TextRange(tokenStart, tokenEnd);
return(result);
}
return(ParseError(tokenizer, "Minus without value", tokenStart.Line, tokenStart.Column));
case '{':
tokenizer.Advance();
return(DictionaryExpression.Parse(tokenizer));
case '[':
tokenizer.Advance();
return(ParseArray(tokenizer));
default:
var line = tokenizer.Line;
var column = tokenizer.Column;
var identifier = tokenizer.ReadIdentifier();
if (identifier.IsEmpty)
{
var error = ParseError(tokenizer, "Unexpected character: " + tokenizer.NextChar);
tokenizer.Advance();
return(error);
}
SkipWhitespace(tokenizer);
if (identifier == "return")
{
clause = ExpressionBase.Parse(tokenizer);
if (clause.Type == ExpressionType.ParseError)
{
return(clause);
}
return(new ReturnExpression(new KeywordExpression(identifier.ToString(), line, column), clause));
}
if (identifier == "function")
{
return(UserFunctionDefinitionExpression.Parse(tokenizer, line, column));
}
if (identifier == "for")
{
return(ForExpression.Parse(tokenizer, line, column));
}
if (identifier == "if")
{
return(IfExpression.Parse(tokenizer, line, column));
}
if (identifier == "true")
{
return(new BooleanConstantExpression(true, line, column));
}
if (identifier == "false")
{
return(new BooleanConstantExpression(false, line, column));
}
if (tokenizer.NextChar == '(')
{
tokenizer.Advance();
var parameters = new List <ExpressionBase>();
ParseParameters(tokenizer, parameters);
var functionCall = new FunctionCallExpression(new FunctionNameExpression(identifier.ToString(), line, column), parameters);
functionCall.Location = new TextRange(line, column, tokenizer.Line, tokenizer.Column - 1);
return(functionCall);
}
if (tokenizer.NextChar == '[')
{
IndexedVariableExpression parent = null;
do
{
tokenizer.Advance();
var index = ExpressionBase.Parse(tokenizer);
if (index.Type == ExpressionType.ParseError)
{
return(index);
}
SkipWhitespace(tokenizer);
if (tokenizer.NextChar != ']')
{
return(ParseError(tokenizer, "Expecting closing bracket after index"));
}
tokenizer.Advance();
SkipWhitespace(tokenizer);
if (parent != null)
{
parent = new IndexedVariableExpression(parent, index);
}
else
{
parent = new IndexedVariableExpression(new VariableExpression(identifier.ToString(), line, column), index);
}
} while (tokenizer.NextChar == '[');
return(parent);
}
return(new VariableExpression(identifier.ToString(), line, column));
}
}
private static ExpressionBase ParseClauseExtension(ExpressionBase clause, PositionalTokenizer tokenizer, OperationPriority priority)
{
do
{
var clauseEndLine = tokenizer.Line;
var clauseEndColumn = tokenizer.Column;
SkipWhitespace(tokenizer);
var joinerLine = tokenizer.Line;
var joinerColumn = tokenizer.Column;
switch (tokenizer.NextChar)
{
case '+':
if (priority == OperationPriority.AddSubtract && clause.Type == ExpressionType.StringConstant)
{
priority = OperationPriority.AppendString;
}
if (priority >= OperationPriority.AddSubtract)
{
return(clause);
}
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Add, joinerLine, joinerColumn);
break;
case '-':
if (priority >= OperationPriority.AddSubtract)
{
return(clause);
}
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Subtract, joinerLine, joinerColumn);
break;
case '*':
if (priority >= OperationPriority.MulDivMod)
{
return(clause);
}
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Multiply, joinerLine, joinerColumn);
break;
case '/':
if (priority >= OperationPriority.MulDivMod)
{
return(clause);
}
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Divide, joinerLine, joinerColumn);
break;
case '%':
if (priority >= OperationPriority.MulDivMod)
{
return(clause);
}
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.Modulus, joinerLine, joinerColumn);
break;
case '=':
if (tokenizer.MatchSubstring("==") == 2)
{
if (priority >= OperationPriority.Compare)
{
return(clause);
}
tokenizer.Advance(2);
clause = ParseComparison(tokenizer, clause, ComparisonOperation.Equal, joinerLine, joinerColumn);
}
else
{
if (priority > OperationPriority.Assign)
{
return(clause);
}
tokenizer.Advance();
if (tokenizer.NextChar == '>')
{
tokenizer.Advance();
clause = AnonymousUserFunctionDefinitionExpression.ParseAnonymous(tokenizer, clause);
}
else
{
clause = ParseAssignment(tokenizer, clause, joinerLine, joinerColumn);
}
}
break;
case '!':
if (priority >= OperationPriority.Compare)
{
return(clause);
}
tokenizer.Advance();
if (tokenizer.NextChar != '=')
{
ParseError(tokenizer, "= expected following !", joinerLine, joinerColumn);
}
else
{
tokenizer.Advance();
clause = ParseComparison(tokenizer, clause, ComparisonOperation.NotEqual, joinerLine, joinerColumn);
}
break;
case '<':
if (priority >= OperationPriority.Compare)
{
return(clause);
}
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 '>':
if (priority >= OperationPriority.Compare)
{
return(clause);
}
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 '&':
if (tokenizer.MatchSubstring("&&") == 2)
{
if (priority >= OperationPriority.And)
{
return(clause);
}
tokenizer.Advance(2);
clause = ParseConditional(tokenizer, clause, ConditionalOperation.And, joinerLine, joinerColumn);
}
else
{
if (priority >= OperationPriority.BitwiseAnd)
{
return(clause);
}
tokenizer.Advance();
clause = ParseMathematic(tokenizer, clause, MathematicOperation.BitwiseAnd, joinerLine, joinerColumn);
}
break;
case '|':
if (priority >= OperationPriority.Or)
{
return(clause);
}
tokenizer.Advance();
if (tokenizer.NextChar != '|')
{
ParseError(tokenizer, "| expected following |", joinerLine, joinerColumn);
}
else
{
tokenizer.Advance();
clause = ParseConditional(tokenizer, clause, ConditionalOperation.Or, joinerLine, joinerColumn);
}
break;
default:
if (clause.Location.End.Column == 0)
{
clause.Location = new TextRange(clause.Location.Start, new TextLocation(clauseEndLine, clauseEndColumn));
}
return(clause);
}
if (clause.Type == ExpressionType.ParseError)
{
return(clause);
}
} while (true);
}