public ITerm Implode(ITerm parseTree)
{
parseTree.IsCons("parsetree", 2);
ITerm result = ImplodeAppl(parseTree[0].ToCons("appl", 2));
return result;
}
/// <summary>
/// Reads the production type from a term.
/// </summary>
/// <param name="term">The term.</param>
/// <returns>The production type.</returns>
private ProductionType ReadProductionType(ITerm term)
{
#region Contract
Contract.Requires<ArgumentNullException>(term != null);
Contract.Ensures(Enum.IsDefined(typeof(ProductionType), Contract.Result<ProductionType>()));
#endregion
if (term.IsCons("no-attrs", 0))
return ProductionType.None;
ProductionType type = ProductionType.None;
IListTerm list = (IListTerm)term.ToCons("attrs", 1)[0];
foreach (var t in list.SubTerms.OfType<IConsTerm>())
{
if (t.SubTerms.Count != 0)
continue;
// TODO: Error when the type is set more than once.
switch (t.Name)
{
case "reject": type = ProductionType.Reject; break;
case "prefer": type = ProductionType.Prefer; break;
case "avoid": type = ProductionType.Avoid; break;
case "bracket": type = ProductionType.Bracket; break;
case "assoc":
{
var a = t[0];
if (a.IsCons("left", 0) || a.IsCons("assoc", 0))
type = ProductionType.LeftAssociative;
else if (a.IsCons("right", 0))
type = ProductionType.RightAssociative;
else if (a.IsCons("non-assoc", 0))
type = ProductionType.None;
else
throw new InvalidOperationException("Unknown associativity: " + a);
}
break;
}
}
return type;
}
/// <summary>
/// Reads the production flags from a term.
/// </summary>
/// <param name="term">The term.</param>
/// <returns>The production flags.</returns>
private ProductionFlags ReadProductionFlags(ITerm term)
{
#region Contract
Contract.Requires<ArgumentNullException>(term != null);
#endregion
if (term.IsCons("no-attrs", 0))
return ProductionFlags.None;
ProductionFlags flags = ProductionFlags.None;
IListTerm list = (IListTerm)term.ToCons("attrs", 1)[0];
foreach (var t in list.SubTerms.OfType<IConsTerm>())
{
if (t.SubTerms.Count != 0)
continue;
switch (t.Name)
{
case "recover": flags |= ProductionFlags.Recover; break;
case "completion": flags |= ProductionFlags.Completion; break;
case "ignore-indent":
case "ignore-layout": flags |= ProductionFlags.IgnoreLayout; break;
case "enforce-newline": flags |= ProductionFlags.NewlineEnforced; break;
case "longest-match": flags |= ProductionFlags.LongestMatch; break;
}
}
return flags;
}
/// <summary>
/// Reads the constructor name from a term.
/// </summary>
/// <param name="term">The term.</param>
/// <returns>The constructor name.</returns>
private string ReadConstructor(ITerm term)
{
#region Contract
Contract.Requires<ArgumentNullException>(term != null);
#endregion
if (term.IsCons("no-attrs", 0))
return null;
IListTerm list = (IListTerm)term.ToCons("attrs", 1)[0];
var consTerms = list.SubTerms.Select(t => t.AsCons("cons", 1)).Where(c => c != null);
IConsTerm consTerm = consTerms.SingleOrDefault();
return consTerm?[0]?.ToString();
}