private static bool HasIllegalPatternVariables(
AnalyzedPattern pattern,
bool permitDesignations = true,
bool isTopLevel = false
)
{
switch (pattern)
{
case Not p:
return(HasIllegalPatternVariables(p.Pattern, permitDesignations: isTopLevel));
case Binary p:
if (p.IsDisjunctive)
{
permitDesignations = false;
}
return(HasIllegalPatternVariables(p.Left, permitDesignations) ||
HasIllegalPatternVariables(p.Right, permitDesignations));
case Source p when !permitDesignations:
return(p.PatternSyntax
.DescendantNodes()
.OfType <SingleVariableDesignationSyntax>()
.Any(variable => !variable.Identifier.IsMissing));
default:
return(false);
}
}
public static AnalyzedPattern?TryCreate(AnalyzedPattern leftPattern, AnalyzedPattern rightPattern, bool isDisjunctive, SyntaxToken token)
{
var target = leftPattern.Target;
if (!SyntaxFactory.AreEquivalent(target.Syntax, rightPattern.Target.Syntax))
{
return(null);
}
return(new Binary(leftPattern, rightPattern, isDisjunctive, token, target));
}
private Not(AnalyzedPattern pattern, IOperation target) : base(target)
=> Pattern = pattern;