public BoundUnaryExpression(SyntaxNode syntax, BoundUnaryOperator @operator, BoundExpression expression)
: base(BoundNodeKind.UnaryExpression, syntax)
{
this.Operator = @operator;
this.Expression = expression;
this.ConstantValue = ConstantFolding.Fold(@operator, expression);
}
public static BoundUnaryExpression Unary(SyntaxNode syntax, SyntaxKind kind, BoundExpression expr)
{
var op = BoundUnaryOperator.Bind(kind, expr.Type) !;
return(new BoundUnaryExpression(syntax, op, expr));
}
private BoundExpression Negate(BoundExpression condition)
{
if (condition is BoundLiteralExpression literal)
{
var value = (bool)literal.Value;
return(new BoundLiteralExpression(condition.Syntax, !value));
}
var op = BoundUnaryOperator.Bind(SyntaxKind.ExmToken, BuiltinTypes.Bool) !;
return(new BoundUnaryExpression(condition.Syntax, op, condition));
}
public static BoundConstant?Fold(BoundUnaryOperator op, BoundExpression rhs)
{
if (rhs.ConstantValue != null)
{
var value = rhs.ConstantValue.Value;
switch (op.Kind)
{
case BoundUnaryOperatorKind.Identity: return(new BoundConstant(/*(int)*/ value));
case BoundUnaryOperatorKind.Negation: return(new BoundConstant(-(int)value));
case BoundUnaryOperatorKind.LogicalNegation: return(new BoundConstant(!(bool)value));
default:
throw new Exception($"Unexpected unary operator '{op.Kind}' for type '{rhs.Type}'");
}
}
return(null);
}
