private static SwitchExpressionArmSyntax AsSwitchExpressionArmSyntax(
AnalyzedSwitchSection section,
Feature feature
)
{
if (section.Labels.IsDefault)
{
return(SwitchExpressionArm(DiscardPattern(), AsExpressionSyntax(section.Body)));
}
var pattern = AsPatternSyntax(section.Labels[0].Pattern, feature);
var whenClause = AsWhenClause(section.Labels[0]);
Debug.Assert(
whenClause == null || section.Labels.Length == 1,
"We shouldn't have guards when we're combining multiple cases into a single arm"
);
for (var i = 1; i < section.Labels.Length; i++)
{
var label = section.Labels[i];
Debug.Assert(
label.Guards.Length == 0,
"We shouldn't have guards when we're combining multiple cases into a single arm"
);
var nextPattern = AsPatternSyntax(label.Pattern, feature);
pattern = BinaryPattern(
SyntaxKind.OrPattern,
pattern.Parenthesize(),
nextPattern.Parenthesize()
);
}
return(SwitchExpressionArm(pattern, whenClause, AsExpressionSyntax(section.Body)));
}
private SyntaxNode AsSwitchSectionSyntax(AnalyzedSwitchSection section, SyntaxGenerator generator)
{
var statements = AsSwitchSectionStatements(section.Body);
return(section.Labels.IsDefault
? generator.DefaultSwitchSection(statements)
: generator.SwitchSectionFromLabels(section.Labels.Select(AsSwitchLabelSyntax), statements));
}
private static SwitchExpressionArmSyntax AsSwitchExpressionArmSyntax(AnalyzedSwitchSection section)
{
// In a switch expression, we expect only a single label
Debug.Assert(section.Labels.IsDefault || section.Labels.Length == 1);
var(pattern, whenClause) = section.Labels.IsDefault
? (DiscardPattern(), null)
: (AsPatternSyntax(section.Labels[0].Pattern), AsWhenClause(section.Labels[0]));
return(SwitchExpressionArm(pattern, whenClause, AsExpressionSyntax(section.Body)));
}
