internal override void WriteTo(CCodeWriterBase c)
{
Local localCase = null;
if (this.stringEquality != null)
{
c.OpenBlock();
var localImpl = new LocalImpl {
Name = "__SwitchExpression", Type = this.expression.Type
};
var local = new Local {
LocalSymbol = localImpl
};
var localImplCase = new LocalImpl {
Name = "__SwitchCase", Type = new TypeImpl {
SpecialType = SpecialType.System_Int32
}
};
localCase = new Local {
LocalSymbol = localImplCase
};
new VariableDeclaration
{
Statements =
{
new ExpressionStatement
{
Expression =
new AssignmentOperator
{
TypeDeclaration = true,
Type = new TypeImpl {
SpecialType = SpecialType.System_Int32
},
Left = localCase,
Right = new Literal{
Value = ConstantValue.Create(0)
}
}
}
}
}.WriteTo(c);
new VariableDeclaration
{
Statements =
{
new ExpressionStatement
{
Expression =
new AssignmentOperator
{
TypeDeclaration = true,
Type = new TypeImpl {
SpecialType = SpecialType.System_String
},
Left = local,
Right = this.expression
}
}
}
}.WriteTo(c);
// first if
IfStatement first = null;
IfStatement last = null;
var caseIndex = 0;
foreach (var switchSection in this.switchCases)
{
foreach (var label in switchSection.Labels)
{
if (label.Value == null)
{
// default case;
continue;
}
caseIndex++;
// compare
var callEqual = new Call()
{
Method = this.stringEquality
};
callEqual.Arguments.Add(local);
callEqual.Arguments.Add(new Literal {
Value = label.Value
});
// set value
var setExpr = new ExpressionStatement
{
Expression =
new AssignmentOperator
{
Left = localCase,
Right = new Literal {
Value = ConstantValue.Create(caseIndex)
}
}
};
var ifStatement = new IfStatement
{
Condition = callEqual,
IfStatements = setExpr
};
first = first ?? ifStatement;
if (last != null)
{
last.ElseStatementsOpt = ifStatement;
}
last = ifStatement;
// remap case value
label.Value = ConstantValue.Create(caseIndex);
}
}
if (first != null)
{
first.WriteTo(c);
}
c.Separate();
}
foreach (var statement in this.statements)
{
statement.WriteTo(c);
}
var generateDefaultLabel = this.isNullableType;
if (this.isNullableType)
{
var nullCase = this.switchCases.FirstOrDefault(sc => sc.Labels.Any(l => l.Value != null && l.Value.IsNull));
if (nullCase != null)
{
generateDefaultLabel = false;
}
var nullCaseOrDefault = nullCase ?? this.switchCases.FirstOrDefault(sc => sc.Labels.Any(l => l.Value == null));
if (nullCaseOrDefault != null)
{
var effectiveExpression = this.expression;
var callExpression = this.expression as Call;
if (callExpression != null)
{
effectiveExpression = new UnaryOperator
{
OperatorKind = UnaryOperatorKind.LogicalNegation,
Operand = new Call {
ReceiverOpt = callExpression.ReceiverOpt, Method = new MethodImpl {
Name = "get_HasValue", Parameters = ImmutableArray <IParameterSymbol> .Empty
}
}
};
}
// we need to insert nullable goto;
var ifStatement = new IfStatement
{
Condition = effectiveExpression,
IfStatements = new GotoStatement {
Label = nullCaseOrDefault.Labels.First(l => l.Value == null || l.Value.IsNull)
}
};
ifStatement.WriteTo(c);
}
}
c.TextSpan("switch");
c.WhiteSpace();
c.TextSpan("(");
if (this.stringEquality != null)
{
localCase.WriteTo(c);
}
else
{
this.expression.WriteTo(c);
}
c.TextSpan(")");
c.NewLine();
c.OpenBlock();
foreach (var switchSection in this.switchCases)
{
if (!generateDefaultLabel && switchSection.Labels.Any(l => l.Value == null))
{
switchSection.IsNullableType = false;
}
switchSection.WriteTo(c);
}
c.EndBlock();
if (this.stringEquality != null)
{
c.EndBlock();
}
c.Separate();
}
internal override void WriteTo(CCodeWriterBase c)
{
Local localCase = null;
if (this.stringEquality != null)
{
c.OpenBlock();
var localImpl = new LocalImpl {
Name = "__SwitchExpression", Type = this.expression.Type
};
var local = new Local {
LocalSymbol = localImpl
};
var localImplCase = new LocalImpl {
Name = "__SwitchCase", Type = new TypeImpl {
SpecialType = SpecialType.System_Int32
}
};
localCase = new Local {
LocalSymbol = localImplCase
};
new VariableDeclaration {
Local = localCase
}.WriteTo(c);
new VariableDeclaration {
Local = local
}.WriteTo(c);
// first if
IfStatement first = null;
IfStatement last = null;
var caseIndex = 0;
foreach (var switchSection in this.switchCases)
{
foreach (var label in switchSection.Labels)
{
if (label.Value == null)
{
// default case;
continue;
}
caseIndex++;
// compare
var callEqual = new Call()
{
Method = this.stringEquality
};
callEqual.Arguments.Add(local);
callEqual.Arguments.Add(new Literal {
Value = label.Value
});
// set value
var setExpr = new ExpressionStatement
{
Expression =
new AssignmentOperator
{
Left = localCase,
Right = new Literal {
Value = ConstantValue.Create(caseIndex)
}
}
};
var ifStatement = new IfStatement
{
Condition =
new BinaryOperator
{
OperatorKind = BinaryOperatorKind.Equal,
Left = new Literal {
Value = ConstantValue.Create(0)
},
Right = callEqual
},
IfStatements = setExpr
};
first = first ?? ifStatement;
if (last != null)
{
last.ElseStatementsOpt = ifStatement;
}
last = ifStatement;
// remap case value
label.Value = ConstantValue.Create(caseIndex);
}
}
if (first != null)
{
first.WriteTo(c);
}
c.Separate();
}
foreach (var statement in this.statements)
{
statement.WriteTo(c);
}
c.TextSpan("switch");
c.WhiteSpace();
c.TextSpan("(");
if (this.stringEquality != null)
{
localCase.WriteTo(c);
}
else
{
this.expression.WriteTo(c);
}
c.TextSpan(")");
c.NewLine();
c.OpenBlock();
foreach (var switchSection in this.switchCases)
{
switchSection.WriteTo(c);
}
c.EndBlock();
if (this.stringEquality != null)
{
c.EndBlock();
}
c.Separate();
}