private CodeStatementCollection GenerateImperativeStatement(SwitchExpression node)
{
var condition = GenerateImperativeExpression(node.Expression);
CodeConditionStatement switchStatement = null;
CodeConditionStatement rootSwitchStatement = null;
Action<CodeConditionStatement> setSwitchStmt = x =>
{
if (switchStatement != null)
{
switchStatement.FalseStatements.Add(x);
switchStatement = x;
}
else
{
rootSwitchStatement = switchStatement = x;
}
};
foreach (var c in node.Cases)
{
var caseChecks = c.Cases
.Cast<IdentifierExpression>()
.Select(x => x.Identifier)
.Select(x => IsTokenType(x) ? (CodeExpression)GetTokenTypeRef(x) : CodeHelper.VarRef(x))
.Select(x => CodeHelper.BinOpExp(condition, CodeBinaryOperatorType.ValueEquality, x))
.ToArray();
var exp = CodeHelper.BinOpExpJoin(caseChecks, CodeBinaryOperatorType.BooleanOr);
var body = GenerateImperativeStatements(c.Body);
//var body = c.Body
// .SelectMany(x => GenerateImperativeStatement(x).OfType<CodeStatement>())
// .ToArray();
setSwitchStmt(new CodeConditionStatement(exp, body.Cast<CodeStatement>().ToArray()));
}
if (node.DefaultCase != null && node.DefaultCase.Any())
{
if (setSwitchStmt == null)
{
throw new NotImplementedException();
}
//var defaultStmts = node.DefaultCase
// .SelectMany(x => GenerateImperativeStatement(x).OfType<CodeStatement>())
// .ToArray();
var defaultStmts = GenerateImperativeStatements(node.DefaultCase)
.OfType<CodeStatement>()
.ToArray();
switchStatement.FalseStatements.AddRange(defaultStmts);
}
return new CodeStatementCollection(new[] { rootSwitchStatement });
}
private void InterpretSwitchExpression(SwitchExpression expression)
{
var exp = (AphidObject)InterpretExpression(expression.Expression);
foreach (var c in expression.Cases)
{
foreach (var c2 in c.Cases)
{
var caseValue = (AphidObject)InterpretExpression(c2);
if (!exp.Value.Equals(caseValue.Value))
{
continue;
}
EnterChildScope();
Interpret(c.Body, resetIsReturning: false);
LeaveChildScope(bubbleReturnValue: true);
return;
}
}
if (expression.DefaultCase != null)
{
EnterChildScope();
Interpret(expression.DefaultCase, resetIsReturning: false);
LeaveChildScope(bubbleReturnValue: true);
}
}
private AphidExpression ParseSwitchExpression()
{
NextToken();
Match(AphidTokenType.LeftParenthesis);
var exp = ParseExpression();
Match(AphidTokenType.RightParenthesis);
Match(AphidTokenType.LeftBrace);
var switchExp = new SwitchExpression()
{
Expression = exp,
Cases = new List<SwitchCase>(),
};
while (_currentToken.TokenType != AphidTokenType.RightBrace)
{
if (_currentToken.TokenType != AphidTokenType.defaultKeyword)
{
var caseTuple = ParseTuple();
Match(AphidTokenType.ColonOperator);
var block = ParseBlock();
switchExp.Cases.Add(new SwitchCase()
{
Cases = caseTuple,
Body = block,
});
}
else
{
NextToken();
Match(AphidTokenType.ColonOperator);
switchExp.DefaultCase = ParseBlock();
}
}
NextToken();
return switchExp;
}