/// <summary>
/// Creates a <see cref="SwitchSection"/> that represents a switch statement section.
/// </summary>
/// <param name="locals">The locals that are in scope of the section.</param>
/// <param name="labels">The labels handled by the section.</param>
/// <param name="statements">The statements in the body of the section.</param>
/// <returns>The created <see cref="SwitchLabel"/>.</returns>
public static SwitchSection SwitchSection(IEnumerable <ParameterExpression> locals, IEnumerable <SwitchLabel> labels, IEnumerable <Expression> statements)
{
var localsList = CheckUniqueVariables(locals, nameof(locals));
var labelsList = labels.ToReadOnly();
RequiresNotEmpty(labelsList, nameof(labels));
RequiresNotNullItems(labelsList, nameof(labels));
var allLabels = new HashSet <LabelTarget>();
var patternInputType = default(Type);
foreach (var label in labelsList)
{
if (label.Label != null && !allLabels.Add(label.Label))
{
throw Error.DuplicateLabelInSwitchSection(label.Label);
}
if (patternInputType == null)
{
patternInputType = label.Pattern.InputType;
}
else if (patternInputType != label.Pattern.InputType)
{
throw Error.InconsistentPatternInputType(label.Pattern.InputType, patternInputType);
}
}
var statementsList = GetStatements(statements);
return(new SwitchSection(localsList, labelsList, statementsList));
}
