/// <summary>
/// Converts conditional statements whose top-most condition is an OR.
/// Creates a nested structure without the top-most OR.
/// </summary>
private (bool, QsConditionalStatement) ProcessOR(QsConditionalStatement conditionStatment)
{
// This method expects elif blocks to have been abstracted out
if (conditionStatment.ConditionalBlocks.Length != 1)
{
return(false, conditionStatment);
}
var(condition, block) = conditionStatment.ConditionalBlocks[0];
if (condition.Expression is ExpressionKind.OR orCondition)
{
var subCondition = new QsConditionalStatement(ImmutableArray.Create(Tuple.Create(orCondition.Item2, block)), conditionStatment.Default);
var subIfStatment = new QsStatement(
QsStatementKind.NewQsConditionalStatement(subCondition),
LocalDeclarations.Empty,
block.Location,
QsComments.Empty);
var newDefault = QsNullable <QsPositionedBlock> .NewValue(new QsPositionedBlock(
new QsScope(ImmutableArray.Create(subIfStatment), block.Body.KnownSymbols),
block.Location,
QsComments.Empty));
return(true, new QsConditionalStatement(ImmutableArray.Create(Tuple.Create(orCondition.Item1, block)), newDefault));
}
else
{
return(false, conditionStatment);
}
}
/// <summary>
/// Converts if-elif-else structures to nested if-else structures.
/// </summary>
private (bool, QsConditionalStatement) ProcessElif(QsConditionalStatement conditionStatment)
{
if (conditionStatment.ConditionalBlocks.Length < 2)
{
return(false, conditionStatment);
}
var subCondition = new QsConditionalStatement(conditionStatment.ConditionalBlocks.RemoveAt(0), conditionStatment.Default);
var secondConditionBlock = conditionStatment.ConditionalBlocks[1].Item2;
var subIfStatment = new QsStatement(
QsStatementKind.NewQsConditionalStatement(subCondition),
LocalDeclarations.Empty,
secondConditionBlock.Location,
secondConditionBlock.Comments);
var newDefault = QsNullable <QsPositionedBlock> .NewValue(new QsPositionedBlock(
new QsScope(ImmutableArray.Create(subIfStatment), secondConditionBlock.Body.KnownSymbols),
secondConditionBlock.Location,
QsComments.Empty));
return(true, new QsConditionalStatement(ImmutableArray.Create(conditionStatment.ConditionalBlocks[0]), newDefault));
}
/// <summary>
/// Converts conditional statements to nested structures so they do not
/// have elif blocks or top-most OR or AND conditions.
/// </summary>
private QsStatement ReshapeConditional(QsStatement statement)
{
if (statement.Statement is QsStatementKind.QsConditionalStatement condition)
{
var stm = condition.Item;
(_, stm) = ProcessElif(stm);
bool wasOrProcessed, wasAndProcessed;
do
{
(wasOrProcessed, stm) = ProcessOR(stm);
(wasAndProcessed, stm) = ProcessAND(stm);
} while (wasOrProcessed || wasAndProcessed);
return(new QsStatement(
QsStatementKind.NewQsConditionalStatement(stm),
statement.SymbolDeclarations,
statement.Location,
statement.Comments));
}
return(statement);
}