protected override BoundExpression RewriteWhileExpression(BoundWhileExpression node)
{
/*
* while <condition>
* <body>
*
* <whileLabel>
* gotoIfFalse <condition> <endLabel>
* <body>
* goto <whileLabel>
* <endLabel>
*/
var body = RewriteExpression(node.Body);
var condition = RewriteExpression(node.Condition);
return(RewriteExpression(
new BoundBlockExpression(
node.Syntax,
ImmutableArray.Create <BoundStatement>(
new BoundLabelStatement(node.Syntax, node.ContinueLabel),
new BoundConditionalGotoStatement(node.Syntax, node.BreakLabel, condition),
new BoundExpressionStatement(node.Syntax, body),
new BoundGotoStatement(node.Syntax, node.ContinueLabel),
new BoundLabelStatement(node.Syntax, node.BreakLabel)
),
new BoundUnitExpression(node.Syntax)
)
));
}
public override void VisitWhileExpression(BoundWhileExpression node)
{
_writer.WriteKeyword("while ");
_writer.WritePunctuation("(");
node.Condition.Accept(this);
_writer.WritePunctuation(") ");
_writer.WriteLine();
WriteNestedExpression(node.Body);
}
public virtual void VisitWhileExpression(BoundWhileExpression node) => this.DefaultVisit(node);
protected override BoundExpression RewriteWhileExpression(BoundWhileExpression node)
{
throw new InvalidProgramException("No `while` expression should exist at this stage");
}
